Journal articles: 'Peroxide cure'

1

Ferradino, Anthony G. "Antioxidant Selection for Peroxide Cure Elastomer Applications." Rubber Chemistry and Technology 76, no. 3 (2003): 694–718. http://dx.doi.org/10.5254/1.3547763.

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Abstract For applications demanding the best high temperature aging performance with lowest compression set, polymers are crosslinked with peroxides. The carbon-carbon bonds that are formed are more thermally stable than crosslinks containing sulfur atoms generated by conventional vulcanization by sulfur- and sulfur based cure systems. However, peroxide crosslinking requires special attention to the selection of compounding ingredients. Materials such as plasticizers, oils, and acidic materials such as silicas and air-floated clays detract from crosslinking efficiency by competing with the polymer for the free radicals produced by peroxides. Antioxidants, as a class, are free-radical scavengers and inhibit peroxide crosslinking. This paper discusses selecting the best antioxidant systems for peroxide cured elastomers by comparing various classes of antidegradants: peroxy and alkoxy radical traps (amines and hindered phenols), hydroperoxide decomposers, and synergists. Among the most effective include: 1) a quinoline polymerized 1,2-dihydro-2,2,4-trimethylquinoline 2) an amine, p-dicumyl-diphenylamine, 3) a hindered phenol, tetrakis (metylene (3,5-di-t-butyl-4-hydroxy-hydrocinnamate)) methane, and 4) a dithiocarbamate, nickel dimethyl-dithiocarbamate. For optimum performance, these are used in combination with the synergist, zinc-2-mercaptotoluimidazole. Also presented is an antioxidant system optimization study using a statistically designed experiment.

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Keller, Robert C. "Peroxide Curing of Ethylene-Propylene Elastomers." Rubber Chemistry and Technology 61, no. 2 (1988): 238–54. http://dx.doi.org/10.5254/1.3536185.

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Abstract 1. Ethylene-propylene elastomers, suitably compounded for extrusion applications, can be readily vulcanized with organic peroxides to meet emerging requirements of improved performance and longer service life. 2. Aralkyl or dialkyl classes of peroxides produce the preferred cure performance, highest physical properties, and lowest compression set. Choice of peroxide governs rate of cure but not necessarily the optimum in crosslinking efficiency. 3. Coagents are essential to the development of optimum cure and stress-strain properties. The bis-maleimide is very effective in compounds that contain significant quantities of process oil, antioxidants for increased heat resistance, or other materials that consume free-radicals. 4. Ethylene-propylene compositional parameters influencing vulcanization activity are the diene, both type and concentration, and the ethylene content. Reactivity of the terpolymers is dependent on the type and amount of diene utilized in the polymer synthesis. High ethylene content improves crosslinking efficiency because there are fewer propylene sequences where chain scission can occur. 5. Increasing levels of hydrocarbon process oil needed in fast extruding compounds require higher peroxide concentrations to maintain cure and stress-strain properties.

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Grima, M. M. Alvarez, A. G. Talma, R. N. Datta, and J. W. M. Noordermeer. "New Concept of Co-Agents for Scorch Delay and Property Improvement in Peroxide Vulcanization." Rubber Chemistry and Technology 79, no. 4 (2006): 694–711. http://dx.doi.org/10.5254/1.3547961.

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Abstract Peroxide cure is an important and widely used cure system for rubber. Several properties obtained via peroxide vulcanization are superior and not achievable with sulfur vulcanization, e.g.: aging resistance, no reversion and low compression set. However, other properties such as tensile strength and dynamic properties, are inferior to those of sulfur vulcanizates. The use of co-agents in peroxide cure leads to a certain extent to improvement in mechanical properties such as tensile strength. Nevertheless the properties are still inferior with respect to mechanical/dynamical properties of sulfur-cured articles. If these properties can be improved, the range of applications of peroxide cure in the rubber industry can be significantly broadened. Scorch is a common problem in peroxide cure, especially for injection molding and extrusion applications. Several additives can help to improve scorch safety, however, they always result in a lower peroxide efficiency, thus inferior vulcanizate properties. In the present study a new concept of co-agents for peroxide vulcanization is introduced. This new concept consists of the use of a combination of a bismaleimide type co-agent, like N,N′-m-phenylenedimaleimide (BMI-MP), and a sulfur containing compound, like dipentamethylenethiuram tetrasulfide (DPTT). This combination provides scorch safety and at the same time improves the mechanical properties of the vulcanizates. Within the bismaleimide type co-agents N,N′-p-phenylenedimaleimide (BMI-PP) provides better mechanical properties than BMI-MP. The concentration of co-agent and sulfur containing compound have a big influence on the scorch time and on the mechanical properties. Optimal properties are reached with 4 phr of co-agent and 0.7 to 0.96 phr of sulfur containing compound.

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Dluzneski, Peter R. "Peroxide Vulcanization of Elastomers." Rubber Chemistry and Technology 74, no. 3 (2001): 451–92. http://dx.doi.org/10.5254/1.3547647.

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Abstract This paper discusses the competing chemical reactions involved in the peroxide vulcanization of elastomers. Each of these reactions can have a profound effect on the cure characteristics as well as on the properties of the final vulcanizate. The balance between these reactions is determined by several factors including the type of polymer, type and concentration of peroxide, cure temperature, and the presence of other compound additives such as co-agents and antidegradants. The effects of all of these factors are discussed.

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Wang, He, Ying Ding, Shugao Zhao, and Claus Wrana. "PEROXIDE CROSS-LINKING OF EPDM USING MOVING DIE RHEOMETER MEASUREMENTS. I: EFFECTS OF THE THIRD MONOMER CONCENTRATION AND PEROXIDE CONTENT." Rubber Chemistry and Technology 88, no. 1 (2015): 40–52. http://dx.doi.org/10.5254/rct.14.85968.

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ABSTRACT The influence of the third monomer 5-ethylene-2-norbornene (ENB) and peroxide content on cure behavior and network structure of peroxide-cured EPDM were investigated by moving die rheometer, NMR relaxation, and dynamic mechanical thermal spectroscopy. According to the rubber elasticity theory, the torque measurement results showed the network structure of peroxide-cured EPDM contained chemical cross-links via combination reaction (Ccom), chemical cross-links via addition reaction (Cadd), and the contribution of entanglement density and network defects to the total cross-link density (CEN). The total cross-link density (Ctot) increased linearly with the peroxide content. The increase of ENB concentration was beneficial for the improvement of cross-linking efficiency of peroxide, but it made the diene conversion of EPDM decrease. CEN was dependent on the third monomer content, which also provided the dominant contribution to the Ctot at low peroxide contents. Furthermore, Ccom and Cadd were dependent on peroxide content linearly, and the latter also was governed by the ENB level.

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Chasey, Kent L. "Rubber Process Oils for Peroxide Curing of Ethylene—Propylene Elastomers." Rubber Chemistry and Technology 65, no. 2 (1992): 385–95. http://dx.doi.org/10.5254/1.3538619.

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Abstract Ten rubber process oils were evaluated in a peroxide-cured EPDM compound. The effects of the process oil on cure-development characteristics and stress—strain properties are discussed. Certain types of molecular structures in the oil can significantly interfere with free-radical vulcanization, and analytical methods for the detection of these structures are provided. The combined effects of the process oil and the peroxide—coagent concentration are also described.

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Rajan, Rejitha, Siby Varghese, and K. E. George. "Kinetics of Peroxide Vulcanization of Natural Rubber." Progress in Rubber, Plastics and Recycling Technology 28, no. 4 (2012): 201–20. http://dx.doi.org/10.1177/147776061202800405.

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This study was undertaken to optimize the vulcanization conditions and explore the effect of residual peroxide in the peroxide vulcanization of natural rubber. The study was followed through the kinetics of the vulcanization reaction at various temperatures viz. 150,155,160 and 165°C. Dicumyl peroxide (DCP) was used as the crosslinking agent. The Monsanto Rheometer was used to investigate the different crosslinking stages and vulcanization kinetics. The thermal decomposition of peroxide followed a first order free radical decomposition reaction. Half-lives at various temperatures were determined. The percentage of residual peroxide was calculated from the cure kinetic data. The effect of residual peroxide on mechanical properties was studied at various peroxide levels and also by extending the cure time (from t90 to t95 and then to t100). Mechanical properties such as tensile strength, elongation at break, modulus and compression set (70 and 100°C) were measured. Excess peroxide was found to cause a high compression set at elevated temperature and the cure time was selected to achieve minimum residual peroxide in the product. Results indicate that peroxide concentration is the dominant factor controlling the crosslink density and hence the properties of the vulcanizates.

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8

Chapman, K. M., and D. J. Jenkin. "Hydrogen Peroxide as a Resin Cure Accelerator." Journal of Adhesion 19, no. 2 (1986): 137–51. http://dx.doi.org/10.1080/00218468608071218.

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9

Pattanawanidchai, Sirichai, Pongdhorn Sae-Oui, Chakrit Sirisinha, and Chomsri Siriwong. "Cure retardation of peroxide-cured silica filled natural rubber influenced by organosilane." Polymer Engineering & Science 59, no. 1 (2018): 42–48. http://dx.doi.org/10.1002/pen.24864.

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10

Kruželák, Ján, Richard Sýkora, and Ivan Hudec. "Peroxide vulcanization of natural rubber. Part II: effect of peroxides and co-agents." Journal of Polymer Engineering 35, no. 1 (2015): 21–29. http://dx.doi.org/10.1515/polyeng-2014-0035.

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Abstract Four types of peroxides in combination with two types of co-agents were used as cross-linking agents for the preparation of rubber compounds based on natural rubber. The effects of Type I and Type II co-agents on cross-linking and physical-mechanical properties of vulcanizates were investigated. The correlation between mechanisms of the interaction of co-agents with the rubber matrix in relation to the characteristics of tested systems was discussed. The results showed that the Type I co-agent influenced the rate and the state of cure. Physical-mechanical properties were improved by addition of the Type I co-agent. By contrast, the Type II co-agent had no contribution to the rate and state of cure. Moreover, physical-mechanical properties of vulcanizates deteriorated in the presence of this type of co-agent.

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11

Tuampoemsab, Surakit, Apaipan Rattanapan, and Pornsri Pakeyangkoon. "Antagonism of Natural Anti- and Pro-Oxidants in Synthetic Polyisoprene Rubber Vulcanizates." Advanced Materials Research 979 (June 2014): 159–62. http://dx.doi.org/10.4028/www.scientific.net/amr.979.159.

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This research was to elucidate the antagonism of natural anti-and pro-oxidants in synthetic polyisoprene rubber (IR) grade 2200 as a model system. Alanine and linoleic acid was chosen as natural anti-and pro-oxidants, respectively. These two amino acids were directly added into the rubber by mixing in two-roll mill. Peroxide vulcanization and three types of the sulfur curing system, i.e., conventional vulcanization (C.V.), efficient vulcanization (E.V.) and semi-E.V. have been studied. Cure properties of the rubber compounds were characterized with moving die rheometer (MDR) at 150 and 170°C for sulfur and peroxide vulcanizing systems, respectively. The compounded rubbers were divided into two parts. The former was pressed on a hydraulic hot press machine and cut to a dumbbell specimen according to ASTM D412 type C. Then, the rubber specimens were subjecting to accelerate the thermal oxidative degradation at 100°C under air-circulating oven with various times. The deterioration of the aged rubber specimens was determined by tensile test. The latter was shaped and characterized by ozone resistance in accordance with ISO 1431/1. For tensile test, the results showed that only the C.V. system of the sulfur cure, the tensile stress at 200% strain of IR comprised alanine and linoleic acid with the ratio of 1:1 was higher predominantly than that of the cured IR control. In addition, the peroxide cured IR mixed with alanine and linoleic acid cannot be passed the heat aging for 96 h. For the ozone resistance, the results exhibited that all specimens appeared uncountable number of crack but only the IR cured by peroxide presented the length of crack less than 1 mm (C-3). It might be concluded from the experiment that anti-oxidative activity of the alanine plays a vital role in the rubber vulcanizate only for C.V. system. However, the existing of both alanine and linoleic acid in the sulfur cured IR was not outstandingly changed for the ozone resistance but not that for the peroxide cured IR.

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12

Maity, M., C. K. Das, K. N. Pandey, and G. N. Mathur. "Polyblends of Polyurethane and EVA Elastomers (Peroxide cure)." International Journal of Polymeric Materials 45, no. 1-2 (2000): 123–33. http://dx.doi.org/10.1080/00914030008034873.

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13

van Drumpt, J. D. "Products and Mechanism of the Thermal Reaction between 2,4-Dichlorobenzoyl Peroxide and n-Pentadecane, an Approximation of the Crosslinking of Silicone Rubbers." Rubber Chemistry and Technology 63, no. 1 (1990): 92–97. http://dx.doi.org/10.5254/1.3538246.

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Abstract Unlike most organic rubbers, viscoelastic silicone rubbers can be either very difficult or impossible to crosslink with sulfur cure systems. Although Pt-catalyzed addition reactions and high-energy radiation curing techniques are available, most heat curing of silicone rubbers is done by means of organic peroxides. Of those, 2,4-dichlorobenzoyl peroxide is the most widely used, due to its versatility, its speed, and the low amount of gaseous decomposition products which it produces. The latter fact allows it to be used for pressureless vulcanization. In fact, 2,4-dichlorobenzoyl peroxide is the only peroxide available on the market that is successfully employed for hot air vulcanization (HAV) of extruded profiles and tubing. In addition, it is widely used in injection, compression, and transfer molding of both vinyl and nonvinyl containing gums. In spite of its widespread use, little factual knowledge is available about the reaction mechanism and products of this peroxide. This is mainly due to the analytical inaccessibility of the crosslinked silicone rubber end product and the evaporation losses caused by processing and curing in (partly) open systems. The present study addresses these issues by using a closed model system. Although many low-molecular-weight polydimethylsiloxanes are available, n-pentadecane was preferred as the substrate because it allowed a direct comparison to be made with similar studies done with other crosslinking peroxides (see e.g., References 2 and 3). The C—H bond strengths in this saturated alkane (410 kJ/mol for primary and 385 kJ/mol for secondary H atoms) were felt, to be close enough to that in polydimethylsiloxanes (approximately 412 kJ/mol) to make it an acceptable model substance for the latter. The system also allowed an estimate to be made of the amount of polychlorobiphenyls (PCBs) that might be formed under normal cure conditions.

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Gibala, David, and Gary R. Hamed. "Cure and Mechanical Behavior of Rubber Compounds Containing Ground Vulcanizates. Part I—Cure Behavior." Rubber Chemistry and Technology 67, no. 4 (1994): 636–48. http://dx.doi.org/10.5254/1.3538699.

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Abstract SBR compounds containing ground vulcanizates of known composition and cure state were prepared and the cure behavior studied. Decreases in scorch times and maximum rheometer torques were observed when ground vulcanizates were added to the SBR compounds. Two primary phenomena are proposed to explain these findings: (1) migration of sulfur from the matrix rubber to the ground vulcanizate (causing torque reduction) and (2) migration of accelerator fragments from the ground vulcanizate to the matrix (causing decreased scorch time). The first proposal is based on direct measurement of sulfur concentrations in both ground particles and the matrix. The second is based on the detection, by high performance liquid chromatography, of mercaptobenzothiazole in the extract from ground vulcanizates. The second also is inferred from the fact that ground vulcanizate particles cured with peroxide do not alter scorch time. Moreover, a compound containing sulfur and ground (accelerated-sulfur vulcanized) rubber, but no added accelerator, nonetheless exhibits acceleration of cure.

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Molloy, Brian M., Kelli-anne Johnson, Rachel J. Ross, and J. Scott Parent. "Functional group tolerance of AOTEMPO-mediated peroxide cure chemistry." Polymer 99 (September 2016): 598–604. http://dx.doi.org/10.1016/j.polymer.2016.07.067.

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Maity, M., B. B. Khatua, and C. K. Das. "Polyblend Systems of Polyurethane and HNBR Elastomers (Peroxide Cure)." International Journal of Polymeric Materials 49, no. 4 (2001): 407–17. http://dx.doi.org/10.1080/00914030108035874.

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Taptim, Kulnida, and Narongrit Sombatsompop. "Antimicrobial performance and the cure and mechanical properties of peroxide-cured silicone rubber compounds." Journal of Vinyl and Additive Technology 19, no. 2 (2013): 113–22. http://dx.doi.org/10.1002/vnl.20320.

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Alvarez Grima, M. M., J. G. Eriksson, A. G. Talma, R. N. Datta, and J. W. M. Noordermeer. "Mechanistic Studies into the New Concept of Co-Agents for Scorch Delay and Property Improvement in Peroxide Vulcanization." Rubber Chemistry and Technology 82, no. 4 (2009): 442–60. http://dx.doi.org/10.5254/1.3548257.

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Abstract In previous studies a new concept of a peroxide cure system for rubber has been reported where scorch safety and mechanical properties are improved at the same time. This new system consists of the use of a combination of a peroxide, a bismaleimide type co-agent and a sulfur spender for the cure of saturated or low-unsaturated rubber. Several mechanical properties have been studied and were found to be improved by using this curing system, such as tensile strength, moduli, compression set and aging. The present paper deals with the understanding of the reported phenomena. Mechanistic studies have been performed with the aim of comprehending the chemistry that takes place during peroxide vulcanization in the presence of a maleimide co-agent and a sulfur spender. From Nuclear Magnetic Resonance and Infrared analysis the loss of the maleimide unsaturation from the co-agent was observed, due to reaction with the sulfur spender. This reaction already takes place at room temperature, thus previous to peroxide decomposition. Further, Model Compound Vulcanization studies were performed using 3-methylpentane as representative model for the saturated rubber backbone. The reaction products of the peroxide vulcanization of 3-methylpentane in the presence of a maleimide type co-agent and a sulfur donor have been analyzed by means of Liquid Chromatography-Mass Spectrometry. Several reaction products have been identified and a reaction mechanism that explains the scorch delay and the property improvement by the new cure system is proposed.

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Nillawong, Manuchet, Pongdhorn Sae-Oui, and Chakrit Sirisinha. "Influences of Coagent Hybrid Ratios and Silanes on Viscoelastic Properties of Silica-Filled HNBR." Advanced Materials Research 747 (August 2013): 564–67. http://dx.doi.org/10.4028/www.scientific.net/amr.747.564.

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Silica filled HNBR compounds were prepared, and modified with 2 different silanes, namely, mercapto silane (TESPT) and vinyl silane (VTEO). Because the HNBR was cured with peroxide, the 2 coagents (TRIM and ZDA) were used simultaneously as a hybrid system for a purpose of cure efficiency enhancement. Various composition ratios of TRIM to ZDA were used in association with 2 different silanes. Results of viscoelastic properties, as investigated by RPA2000 via oscillatory shear flow, suggest the different suitability of coagent hybrid ratio in the system with different silanes. Due to the released sulfur molecules from TESPT, a cure retardation phenomenon is resulted. The use of high ZDA composition leads to improved viscoelastic and cure properties in TESPT filled system. On the other hand, the system modified with VTEO reveals the synergistic effect of VTEO and TRIM, probably via a co-crosslink, resulting in the enhanced crosslink density, especially at high composition ratio of TRIM.

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Sato, Takashi, Akio Fujino, Sachio Hayashi, Motofumi Oyama, and Katsumichi Ono. "Simulation of Crosslink and Graft Mechanism of Hydrogenated-NBR/ZINC Di-Methacrylate Composites by Moving Die Rheometer." Rubber Chemistry and Technology 75, no. 5 (2002): 943–54. http://dx.doi.org/10.5254/1.3547694.

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Abstract This paper studies the crosslink and graft mechanism of hydrogenated-NBR/zinc di-methacrylate (HNBR/ZDMA) composites. The experiments to determine the rate constants of crosslink and graft reaction formulas are from Moving Die Rheometer (MDR) data. Comparison with experimental data and the solution of simultaneous ordinary differential equations for the crosslink and graft reactions are performed. Genetic algorithm optimization of the reaction rate constants allowed for simulation of crosslinking and graft reaction process. This simulation predicts that the HNBR/peroxide cure system will contain 0.1052-mole/l crosslink between matrix HNBR polymer at 2 phr.-peroxide concentration. The crosslink concentration of 0.1052-mole/l is composed of 0.0308-mole/l-addition reaction and 0.0744-mole/l-termination reaction. Moreover, the HNBR/ZDMA cure system contains 0.0148-mole/l graft of poly-ZDMA to HNBR and 0.0903-mole/l crosslink between matrix HNBR polymer at a 2 phr.-peroxide concentration.

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Gan, S. Ian, and Lawrence M. Price. "Waiting-List Induced Proctitis: The Hydrogen Peroxide Enema." Canadian Journal of Gastroenterology 17, no. 12 (2003): 727–29. http://dx.doi.org/10.1155/2003/716490.

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Hydrogen peroxide is a widely available disinfectant that has been reported to cause colitis. We report a case of a 67-year-old man who presented with an acute proctitis caused by a self-inflicted 3% hydrogen peroxide enema. The patient’s intention was to cure himself of a recently diagnosed prostate cancer, because the waiting list for oncological consultation was deemed too long. The pathogenesis of hydrogen peroxide mucosal injury and a review of the literature is discussed.

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Sun, Yu, Chengkai Fan, Benqian Wei, Chrys Wesdemiotis, and Li Jia. "Activated Isobutylene-Isoprene Rubber—Synthesis, Peroxide Cure, and Mechanical Properties." ACS Applied Polymer Materials 2, no. 11 (2020): 5163–72. http://dx.doi.org/10.1021/acsapm.0c00906.

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Joseph, Anu Mary, Benny George, K. N. Madhusoodanan, and Rosamma Alex. "CURE CHARACTERISTICS OF DEVULCANIZED RUBBER:THE ISSUE OF LOW SCORCH." Rubber Chemistry and Technology 90, no. 3 (2017): 536–49. http://dx.doi.org/10.5254/rct.17.83737.

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ABSTRACT We investigate the reasons behind the observed low scorch during the revulcanization of devulcanized rubber. Mechanically devulcanized carbon black filled natural rubber vulcanizates originally cured by conventional vulcanization (CV), semiefficient vulcanization (semi EV), efficient vulcanization (EV), and peroxide systems as well as buffing dust obtained from pre-cured tread with known formulation were used. Revulcanization of these devulcanized samples using sulfur/sulfonamide system led to the following observations; irrespective of the type of sulfur cure system used for the initial vulcanization of the rubber, (i) the devulcanized samples cured without pre-vulcanization induction time and (ii) devulcanized samples prepared from peroxide vulcanized rubber cured with scorch safety. Based on the earlier reports that solvent extraction of devulcanized rubber did not improve the scorch time during revulcanization, the role of zinc bound non-extractable moieties was investigated using devulcanized rubber prepared from activator-free vulcanizates, which disproved the role of such moieties. This confirmed that the scorch reducing moieties should be attached to the rubber main chain, which can be unreacted crosslink precursors and cyclic sulfides left after the initial accelerated sulfur vulcanization of the original sample. The ability of pre-vulcanization inhibitor to induce scorch safety when devulcanized rubber is revulcanized as such, without adding any virgin rubber, proved that mercaptobenzothiazole (MBT) generated from crosslink precursors is the cause of low scorch. Acetone extracted devulcanized rubber samples prepared from tetramethyl thiuramdisulfide (TMTD) cured natural rubber, which does not follow the MBT pathway when revulcanized, cured with scorch safety, which further proved the role of MBT. Based on the previous reports and our results, it is obvious that powdering of rubber vulcanizate and devulcanization processes have no role on the low process safety of these materials, but it is inherent to the initial accelerated sulfur vulcanization chemistry undergone by these materials.

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Khorova, E. A., and A. V. Myshlyavtsev. "Application of hydrogenated butadiene-nitrile rubbers for products operated at high temperatures and in aggressive environments." Voprosy Materialovedeniya, no. 3(95) (January 10, 2019): 129–36. http://dx.doi.org/10.22349/1994-6716-2018-95-3-129-136.

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The subject of the study were rubber mixtures based on hydrogenated butadiene-nitrile rubbers (HNBR) Therban, Zetpol, NBR-B with an acrylonitrile (AN) content of 34% to 49% and unsaturation of 0.9% to 22% with sulfuric, peroxide and sulfuric-peroxide cure systems. The purpose of the study was to determine the effect of the AN content and the degree of unsaturation of HNBR on the properties of rubbers in products designed for operation under the influence of fuels and oils at increased temperatures.The results of the determination of the mass swelling of rubbers in hydrocarbon media and the relative elongation in the process of thermal aging in air and in oil at increased temperatures are presented. The conclusion was made on the use of HNBR mixture with maximum content of AN (49%), with low (6%) and extremely low (0.9%) ODS content and sulfuric peroxide cure system to extend the product service temperature limit to 150°C.

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Azaar, K., J. M. Vergnaud, and I. D. Rosca. "Anisotropic Swelling of EPDM Rubber Discs by Absorption of Toluene." Rubber Chemistry and Technology 76, no. 4 (2003): 1031–44. http://dx.doi.org/10.5254/1.3547768.

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Abstract Anisotropic swelling is observed when thin ethylene propylene diene monomer discs are immersed in a liquid such as toluene, whatever the percent peroxide acting as the curing agent ranging from 2 to 20. The process is studied either by experiments or calculation. The process of absorption is controlled by transient radial and longitudinal diffusion, with a concentration-dependent diffusivity and a finite and constant coefficient of convective transfer at the liquid-rubber interface. The problem is thus complex with a moving boundary since a rather high swelling takes place during the stage of absorption, leading to an increase in dimensions of the flat discs. The increase in the thickness of the discs is around 1.17– 1.18 times larger than that in the radius, at every time, while the diffusivity is the same for the radial and longitudinal transport. The extent of the change in the volume resulting from the toluene absorption varies from 1 to 1.5 depending on the value of the percent peroxide, the lower volume being obtained for the higher value of the curing agent The diffusivity is about the same whatever the percent curing agent. The state of cure is around 96 as obtained by calculation taking into account the heat transfer and the kinetics of the cure reaction. The kinetics of the cure reaction has been determined by measurements made either with a moving die rheometer run under isothermal conditions at three temperatures selected within the 170–190 °C temperature window, or a calorimeter in scanning mode. This fact can be explained by an orientation of the polymeric chains obtained during the cure, resulting from the pressure of the slabs of the heating press. Various percent peroxide as a vulcanizing agent have been used, e.g., 2, 10, and 20%.

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Walton, Kim L., Morgan M. Hughes, and Deepak R. Parikh. "A New Class of Ethylene—Propylene—Diene Terpolymers Produced from Constrained Geometry Metallocene Catalysts." Rubber Chemistry and Technology 74, no. 4 (2001): 688–700. http://dx.doi.org/10.5254/1.3544967.

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Abstract Until recently, ethylene/propylene/diene (EPDM) terpolymers have been manufactured exclusively using vanadium based Ziegler—Natta catalyst systems. The vanadium based catalysts are known to have both product and process limitations. These limitations are due to a complex combination of factors including monomer reactivity, catalyst activity, reactor temperatures and pressures. Single-site metallocene constrained geometry catalyst (CGC) technology enables the manufacture of EPDM terpolymers at higher reactor temperature and catalyst efficiency than standard Ziegler—Natta catalyst systems. The unique combination of monomer, catalyst and process technology enables the manufacture of highly crystalline EPDMs having ethylene contents over 90 wt %. This study investigated these new highly crystalline EPDM terpolymers and their differentiation from commercially available EPDMs. The results indicated that these new EPDMs had very high green strength and barrier properties, yet could be cured by conventional vulcanization techniques. The cure response of these EPDMs to either peroxide or sulfur increased with increasing ethylene content. Sulfur cured vulcanizates had much higher tensile strength than peroxide cured vulcanizates. These new EPDMs demonstrated utility as additives to enhance the abrasion, hot tear, and tensile properties of natural rubber compounds. Sponge compounds, having the unique combination of polyethylene physical properties and the utility of sulfur vulcanization were developed from these new polymers.

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Maity, M., and C. K. Das. "SPECIALTY POLYBLEND SYSTEMS OF POLYURETHANE RUBBER AND ETHYLENE ACRYLIC RUBBER (PEROXIDE CURE)." Polymer-Plastics Technology and Engineering 40, no. 1 (2001): 39–51. http://dx.doi.org/10.1081/ppt-100000118.

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Maity, M., and C?K Das. "Speciality polymer blends of polyurethane elastomers and chlorinated polyethylene rubber (peroxide cure)." Polymer International 49, no. 7 (2000): 757–62. http://dx.doi.org/10.1002/1097-0126(200007)49:7<757::aid-pi451>3.0.co;2-0.

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29

Sirisinha, Chakrit, Sireethorn Phoowakeereewiwat, and Pongdhorn Saeoui. "Cure and dynamic mechanical properties in peroxide-cured isoprene rubber: effects of stearic acid and amine-based antioxidant." European Polymer Journal 40, no. 8 (2004): 1779–85. http://dx.doi.org/10.1016/j.eurpolymj.2004.03.002.

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Widiatma, Ridha Ramadina, Muhammad Yulianto Listiawan, Dwi Murtiastutik, et al. "The Efficacy of Lactobacillus plantarum as Adjunctive Therapy of Bacterial Vaginosis: A Double-blind, Randomized, Placebo-controlled Trial." Berkala Ilmu Kesehatan Kulit dan Kelamin 32, no. 3 (2020): 214. http://dx.doi.org/10.20473/bikk.v32.3.2020.214-220.

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Background: Bacterial vaginosis (BV) is a clinical syndrome caused by the changing of Lactobacillus spp., a producer of hydrogen peroxide, in the normal vagina with a high concentration of anaerobic bacteria, Gardnerella vaginalis and Mycoplasma hominis. This study reports a resistance of BV therapy regimens, high recurrence rates, and side effects of an antibiotic. Therefore, adjunctive therapy for BV management is needed. Research has reported the therapeutic effects of probiotic in BV; however, the results are inconsistent. Purpose: To evaluate the efficacy of standard therapy using metronidazole and Lactobacillus plantarum for BV measured by the cure rate and vaginal flora balance. Methods: A randomized, double-blind, placebo-controlled trial, 30 subjects were randomized to take metronidazole 500 mg twice a day for seven days with weekly evaluation. The Lactobacillus plantarum or placebo group was evaluated every 4 weeks. The cure rate and vaginal flora balance were evaluated using the Amsel criteria and Nugent score before and after the intervention. Result: A total of 30 subjects returned for 28-day follow-up, of which 60% subjects of the antibiotic/probiotic group were cured compared to 40% in the antibiotic/placebo group (p>0.05). Conclusion: There was no difference in the increase of cure rate and vaginal flora balance between the treatment group and significant control group.

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Farsane, Mohamed, Lhasnaoui Soufia, Abdellah Anouar, Souad Chah, Said Dagdag, and Miloudi Bouzziri. "Experimental Evaluation of the Curing of Unsaturated Polyester Resin at Various Amounts of Methyl Ethyl Ketone Peroxide, Cobalt Octoate and Porcelain Powder." Revista de Chimie 71, no. 10 (2020): 58–66. http://dx.doi.org/10.37358/rc.20.10.8350.

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The goal of this research is to investigate the impact of the three parameters on the cure of the unsaturated polyester resin. The obtained values show the influence of each parameter on the cure and hence enables to establish a time-range with regard of the percentage of the components for a good management of the curing process.

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Abdullah, Iram. "DSC Cure Kinetics of an Unsaturated Polyester Resin Using Empirical Kinetic Model." Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences 58, no. 2 (2015): 99–105. http://dx.doi.org/10.52763/pjsir.phys.sci.58.2.2015.99.105.

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In this paper, the kinetics of curing of unsaturated polyester resin initiated with benzoyl peroxide was studied. In case of unsaturated polyester (UP) resin, isothermal test alone could not predict correctly the curing time of UP resin. Therefore, isothermal kinetic analysis through isoconventional adjustment was used to correctly predict the curing time and temperature of UP resin. Isothermal kinetic analysis through isoconversional adjustment indicated that 97% of UP resin cures in 33 min at 120 °C. Curing of UP resin through microwaves was also studied and found that 67% of UP resin cures in 1 min at 120 °C. The crosslinking reaction of UP resin is so fast at 120 °C that it becomes impossible to predict correctly the curing time of UP resin using isothermal test and the burial of C=C bonds in microgels makes it impossible to be fully cured by microwaves at 120 °C. The rheological behaviour of unsaturated polyester resin was also studied to observe the change in viscosity with respect to time and temperature.

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Sengupta, Saurav, Mohamed Esseghir, and Jeffrey M. Cogen. "Effect of formulation variables on cure kinetics, mechanical, and electrical properties of filled peroxide cured, ethylene-propylene-diene monomer compounds." Journal of Applied Polymer Science 120, no. 4 (2010): 2191–200. http://dx.doi.org/10.1002/app.33475.

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Marzocca, A. J., A. L. Rodriguez Garraza, P. A. Sorichetti, C. L. Matteo, and H. O. Mosca. "ABOUT THE CURE KINETICS AND DIELECTRIC RELAXATION SPECTROSCOPY IN COMPOUNDS OF POLYBUTADIENE (BR) WITH DICUMYL PEROXIDE." Anales AFA 23, no. 2 (2013): 75–79. http://dx.doi.org/10.31527/analesafa.2013.23.2.75.

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Abdelhady, A., Z. Eldin, and E. Youssry. "Cure brain cancer by active Brain cancer receptor and induce apoptosis by hydrogen peroxide and B12." Brain Stimulation 8, no. 2 (2015): 323. http://dx.doi.org/10.1016/j.brs.2015.01.049.

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Brouzi, A. El, R. Granger, and J. M. Vergnaud. "Diffusion of the Curing Agent through two Epdm Rubber Sheets with Different% Peroxide during their Simultaneous Cure." Polymers and Polymer Composites 17, no. 8 (2009): 495–504. http://dx.doi.org/10.1177/096739110901700804.

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Zhang, Xiaohu, Hongmei Yang, Yihu Song, and Qiang Zheng. "Assessment of hindered phenol antioxidants on processing stability of peroxide-cure LDPE by rheology and DSC analysis." Journal of Applied Polymer Science 126, no. 3 (2012): 939–46. http://dx.doi.org/10.1002/app.36978.

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Jalkanen, Tero. "Isoconversional kinetic analysis for determining the rate of cross-linking for Pt and peroxide cure silicone rubbers." Thermochimica Acta 703 (September 2021): 178982. http://dx.doi.org/10.1016/j.tca.2021.178982.

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Imanifar, Marzieh, Saeed Ostad Movahed, and Ali Ahmadpour. "Effects of peroxide and phenolic cure systems on characteristics of the filled ethylene-propylene-diene monomer rubber (EPDM)." Journal of Applied Polymer Science 135, no. 21 (2018): 46213. http://dx.doi.org/10.1002/app.46213.

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Xue, Xiao, Qing Xiu Jia, and Guo Liang Zhao. "Preparation and Properties of DCP-Crosslinked Biobased Polyamide." Advanced Materials Research 634-638 (January 2013): 1037–43. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.1037.

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In this work, a new bio-based hybrid polyamide (BDIS) was prepared and was cross-linked by dicumyl peroxide (DCP) with dose ranging from 1 to 7%. The state of cure was observed in vulcameter, and the vulcanization condition was determined subsequently. The cross-linking efficiency of BDIS/DCP blends was assessed using torque, gel content measurements and infrared spectroscopy (FTIR). DCP dose below 1% was not sufficient to reach gelation. Over 1%, the gel content increased with increasing DCP dose. The cross-linked BDIS films exhibited enhanced toughness and mechanical properties compared to precursors. Optimal mechanical properties were obtained with concentration of about 5 wt % DCP. At higher doses, the tensile strength and the elongation at break were decreased due to scission reactions.

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Zhao, Xue, Zhen-Zhen Qiao, and Jin-Xin He. "Preparation of Chitosan Biguanidine Hydrochloride and Application in Antimicrobial Finish of Wool Fabric." Journal of Engineered Fibers and Fabrics 5, no. 3 (2010): 155892501000500. http://dx.doi.org/10.1177/155892501000500303.

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Chitosan biguanidine hydrochloride (CGH) has been synthesized by the guanidinylation reaction of chitosan with dicyandiamide. Its synthetic mechanism was discussed. The structures of CGH were characterized by FT-IR and 13CNMR. In this study, we used citric acid (CA) as a crosslinking agent, mixed with CGH to perform a pad-dry-cure treatment on wool fabric to study its antimicrobial effects with the help of scanning electron microscopy (SEM). The result showed that there was no obvious sign that CGH adhered to the wool fabric if the wool fabrics were not oxidized by hydrogen peroxide. The surface crosslinks of the oxidized wool fibers were relatively coarse, which beneficial for the antimicrobial and antiseptic effects of the wool fabrics. Key words: chitosan biguanidine hydrochloride; synthesis; wool; antimicrobial

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Neppel, A. "Prediction of Equilibrium Swelling in Fuel and Lubricant Ingredients." Rubber Chemistry and Technology 59, no. 1 (1986): 46–69. http://dx.doi.org/10.5254/1.3538188.

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Abstract In accord with the Porter equation, linear relationship has been found between the apparent and actual network-chain concentrations of DCP-cured NBR reference elastomers containing 18–39% ACN and 0–70 phr N550 black while Porter's k factors and, therefore, the extent of the restriction of swelling by the filler vary somewhat with the diluent. Taking this variation into account, a self-consistent relationship has been obtained between data on swelling in MEK (24 h) and those on equilibrium swelling in some fuel and lubricant ingredients (2 to 4 weeks). By using this relationship and the modified Flory-Rehner equation, the equilibrium swelling in fuel and lubricant ingredients of NBR test vulcanizates can be estimated from determining their nitrile content and from an MEK immersion test if these vulcanizates are filled with only N550 black, and if the only variables in their compositions are nitrile content, state of peroxide cure, and carbon black loading. The development of a similar technique to predict the swelling in mixed solvents of unknown NBR vulcanizates would probably involve serious difficulties which would stem from the presence of plasticizers, antioxidants, and fillers other than N550 black as well as from the assessment of the polymer-solvent interaction factor.

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Pazur, Richard J., and T. Mengistu. "INFLUENCE OF THE CROSSLINK STRUCTURE ON THE ACTIVATION ENERGY CALCULATED UNDER THERMO-OXIDATIVE CONDITIONS." Rubber Chemistry and Technology 91, no. 1 (2018): 205–24. http://dx.doi.org/10.5254/rct-17-83714.

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ABSTRACT A series of six carbon black reinforced brominated poly(isobutylene-co-isoprene) (BIIR) compounds has been developed varying only in cure system type: sulfur, sulfur donor, zinc oxide, peroxide, phenolic resin, and ionic. Compounds were aged from room temperature up to 115 °C, and hardness, mechanical properties, and network chain density were measured. Non-Arrhenius behavior was observed due to data curvature from 70 to 85 °C. The oxidation process was adequately described by assigning low (23–85 °C) and high (85–115 °C) temperature regimes. Heterogeneous aging due to diffusion limited oxygen (DLO) occurred for heat aging above 85 °C, and all measured responses except tensile strength were strongly affected, causing lower activation energies. The activation energy for the high temperature oxidation process is in the range of 107 to 133 kJ/mol in the following ascending order: zinc oxide, ionic, sulfur donor, sulfur, peroxide, and resin. The midpoint of the high temperature activation energies is of the same order as the BIIR and poly(isobutylene) elastomers. The low temperature activation energy is in the range of 55–60 kJ/mol and is likely due to a combination of oxidative chain scission (crosslink density loss) and crosslinking recombination (network building) reactions. Apart from the crosslink structure stability, the presence of unsaturation along the polymer chain after vulcanization affects the high temperature activation energy.

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Rodgerd, Phawasoot, Sutaporn Yakkul, and Jitladda Sakdapipanich. "Application of Macca Charcoal in Saponified Natural Rubber Composites." Advanced Materials Research 844 (November 2013): 149–53. http://dx.doi.org/10.4028/www.scientific.net/amr.844.149.

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This present work is an attempt to study the composite between natural rubber (NR) and Macca charcoal, as a special additive, for producing the adhesive plaster for pain relief. The NR latex used in this work was a saponified NR (SPNR) cured by peroxide to avoid allergenic problems in human use, which causes by protein and accelerator in sulphur cure. Macca charcoal is proved to have ability to generate far infrared rays (FIR) in the range of 6-14 µm which can transfer to be heat energy. The human body can absorb FIR in this range because of their deep penetrating ability. Light energy is changed to thermal energy when FIR penetrates through skin to the subcutaneous tissues. This thermal energy helps to decrease the symptoms of stress and fatigue such as headaches, joint pain, burns, muscle spasms, and insomnia. In this work, the SPNR/Macca composite was subjected to studying the effect of Macca charcoal content on the physical and thermal properties of SPNR composites. The results showed that hardness and tensile properties increased with increasing an addition of Macca charcoal in SPNR. In addition, the increasing of Macca charcoal content enhance thermal retention estimation and thermal intensity, but has no substantial effect on depth of FIR diffusion on pork layer. Thus, SPNR/Macca charcoal composites can be an optional material apply for an adhesive bandage for pain relief purpose.

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Adanir, Necdet, Hakan Türkkahraman, and Ahmet Yalçın Güngör. "Effects of Fluorosis and Bleaching on Shear Bond Strengths of Orthodontic Brackets." European Journal of Dentistry 01, no. 04 (2007): 230–35. http://dx.doi.org/10.1055/s-0039-1698344.

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ABSTRACTObjectives: To evaluate the effects of fluorosis and bleaching on shear bond strengths of orthodontic brackets.Methods: A total of 45 (30 fluorosed and 15 non-fluorosed) non-carious freshly extracted human permanent premolar teeth which were extracted for orthodontic reasons and without any caries or visible defects were used in this study. Fluorosed teeth were selected according to the modified Thylstrup and Fejerskov index (TFI), which is based on the clinical changes in fluorosed teeth. First group consisted of 15 fluorosed teeth. Second group of fluorosed teeth were bleached with a 35% hydrogen peroxide office bleaching agent. Third group served as control. No bleaching procedure was applied. Orthodontic brackets were bonded with a light cure composite resin and cured with a halogen light. After bonding, shear bond strengths of the brackets were tested with Universal testing machine.Results: The results showed that fluorosis only and bleaching of fluorosed teeth significantly reduced the bond strengths of the orthodontic brackets (P>.001). Although bleaching of fluorosed teeth decreased the values more, no statistically significant difference was found between fluorosis group and fluorosis+bleaching group (P<.05).Conclusions: Fluorosis and bleaching of fluorosed teeth reduce bracket bond strength to enamel, but the bond strength with these still exceed the minimum 6 to 8 MPa required to expect adequate clinical performance. (Eur J Dent 2007;1:230-235)

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Thongpin, Chanchai, Achiraya Muanwong, Jatuporn Yanyongsak, and Pongsakorn Lorphaitoon. "Effect of ENR Contents on Cure Characteristic and Properties of NR/ENR/EVA Foam." Materials Science Forum 889 (March 2017): 45–50. http://dx.doi.org/10.4028/www.scientific.net/msf.889.45.

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This research studied foaming of natural rubber (NR), epoxidized natural rubber (ENR) and ethylene vinyl acetate copolymer (EVA) blends vulcanizate. The contents of NR/ENR/EVA investigated were 60/10/30, 70/10/20, 50/20/30 and 60/20/20 to keep NR based to 70 and 80 % by weight whereas EVA contents were 20 and 30 % by weight. ENR used in this research was ENR 50. The content of ENR was varied as 10 and 20 % by weight with restpect to total polymer content. The Efficient vulcanization and peroxide systems were used for rubber vulcanization in order to cure both rubber and EVA. Oxydibenzenesulfonyl hydrazide (EW or OBSH) was used as foaming agent. The results showed that rubber blends with 20% ENR tended to show better compatibilization between NR and EVA. The viscosity of rubber blend which indicated by minumum torque was increased with the content of ENR. Cell size of rubber blends foam containing ENR 20 % showed rather normal distribution than ENR 10%. Foam with high content of NR based rubber showed slightly higher density than the other systems. Tensile properties of rubber blends foam were dependent upon NR based contents and compatibility between NR and EVA. Rubber blends foam with high ENR content showed higher specific secant modulus. The specific tensile strength and elongation at break were slightly inferior. The specific tear resistance of the rubber foam was independent on compatibility. High EVA content reduced both specific compressive modulus and compressive strength of the foam. For the foam that contained EVA domain showed permanent deformation and hence high in compression set. Compatibilized rubber blend foams and the foam with high EVA possessed low ball rebound resilience.

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Wu, Wei Li, and Lei Tian. "Preparation of EPDM Flame-Resistant Cable Materials." Applied Mechanics and Materials 151 (January 2012): 240–44. http://dx.doi.org/10.4028/www.scientific.net/amm.151.240.

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EPDM cable materials were prepared, in which EPDM was used as raw materials, silica as a reinforcement, sulfur and dicumyl peroxide (DCP) as the curing agent, aluminum hydroxide (ATH) and magnesium hydroxide (MH) as the flame retardants. The best content and cure parameters of EPDM cable materials were determined by testing hardness, tensile strength, elongation at break, thermal properties and oxygen index, as well as analyzing SEM. The results showed that the properties of EPDM cable materials with DCP were better than those with sulfur or sulfur / DCP blend. The flame retardance of EPDM cable materials with ATH / MH blend was better than that with ATH or MH. The ideal formula of EPDM flame-resistant cable material was EPDM 100 phr, silica 45 phr, DCP 3.5 phr, ATH 90 phr and MH 10 phr. The best curing conditions were at 170 °C under 1.2 MPa for 10 min.

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Xie, Yuefeng, Yan Guo, ShiDong Cao, et al. "Hydroxysafflor Yellow A Attenuates Hydrogen Peroxide-Induced Oxidative Damage on Human Umbilical Vein Endothelial Cells." Evidence-Based Complementary and Alternative Medicine 2020 (November 4, 2020): 1–8. http://dx.doi.org/10.1155/2020/8214128.

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Oxidative stress of endothelial cells is thought to be a principal cause that induces many cardiovascular diseases. Hydroxysafflor yellow A (HSYA) is a major active component in traditional Chinese medicine safflower and has been used to cure ischemic cardiovascular diseases in China for many years. This study aims to investigate whether HSYA has a repairing effect on oxidative damage of human umbilical vein endothelial cells (HUVECs) induced by H2O2 and to provide a theoretical basis for the clinical treatment of cardiovascular diseases related to traditional Chinese medicine. Based on the establishment of an H2O2-induced HUVEC oxidative injury model, the cell viability and proliferation rate were measured by the MTT assay and EdU staining. The intracellular GSH/GSSG ratio and SOD activity were determined by kits. The ROS level was detected by flow cytometry. And the BAX, Bcl-2, PTEN, and AKT expressions were evaluated with western blotting methods. The results showed that HSYA treatment significantly attenuated the H2O2-induced HUVEC cell damage, increased the intracellular GSH/GSSG ratio and unit SOD activity also, and decreased the intracellular ROS levels. Furthermore, HSYA increased the expressions of AKT and Bcl-2 proteins and inhibited the expressions of BAX and PTEN proteins. These suggest that HSYA exerts repair effects on H2O2-induced oxidative damage in HUVECs, and the mechanisms may be related to the influence of BAX/Bcl-2 expression and AKT/PTEN signal pathway expression.

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Khalid, Shah, Aparna Alia, Shrivastava Pn, Muzafar Akbar Rather, and Muzafar Ah Sheikh. "EVALUATION OF IN VITRO ANTIOXIDANT ACTIVITY AND ESTIMATION OF TOTAL PHENOL AND FLAVONOID CONTENT OF ETHANOLIC LEAF EXTRACT OF IRIS KASHMIRIANA." Asian Journal of Pharmaceutical and Clinical Research 10, no. 8 (2017): 309. http://dx.doi.org/10.22159/ajpcr.2017.v10i8.18268.

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Objective: The main aim of this study was to determine the in vitro antioxidant activity of Iris kashmiriana ethanolic leaf extract and also total phenol and flavonoid content was evaluated.Methods: Total phenol content (TPC) was determined by Folin–Ciocalteu method, total flavonoid content (TFC) was estimated by aluminum trichloride spectrophotometer method. Furthermore, antioxidant activity was revealed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, hydrogen peroxide (H2O2) scavenging activity, and reducing power assay.Results: The ethanolic leaf extract of I. kashmiriana showed TPC of 13.25±0.57 μg/100 μg gallic acid equivalents and TFC of 33.61±3.37 μg/100 μg rutin equivalents. The DPPH assay revealed IC50 of 0.418 mg/ml and for H2O2 radical scavenging IC50 was 0.476 mg/ml for the plant extract while as reducing power assay revealed concentration-dependent absorption values which clearly determine the antioxidant property of plant.Conclusion: From the results, it is apparent that I. kashmiriana ethanolic leaf extract possessed potential antioxidant activity which can be used to cure wide range of diseases.

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Rais, C., C. Slimani, M. Benidir, et al. "Seeds of Zizyphus lotus: In Vivo Healing Properties of the Vegetable Oil." Scientific World Journal 2020 (June 8, 2020): 1–8. http://dx.doi.org/10.1155/2020/1724543.

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The present study has been undertaken in order to highlight the healing effect of Zizyphus lotus vegetable oil. The seeds of this plant contain an oil rate of 30%. The obtained results on the main elements composing the vegetable oil have shown that Zizyphus lotus vegetable oil has a low value of acidity index and it presents a not negligible degree of unsaturation. The value of the peroxide index of Zizyphus lotus vegetable oil is less than 10 which characterizes the most of conventional oils. Furthermore, the spectral analysis by gas chromatography has shown the presence of 53 majority and minority molecules. Thus, the evaluation of the healing activity of Z. lotus seed vegetable oil has demonstrated a highly significant effect against the negative control and silver sulfadiazine was used as conventional treatment for burns. Based on the obtained results, we can suggest that the oil extracted from the seeds of the studied plant could be used to cure wounds.

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Journal articles on the topic 'Peroxide cure'

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