Journal articles: 'Isobutene polymer'

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Hejtmánková, Alena, Karel Jeřábek, and Karel Setínek. "Kinetics of methyl tert. butyl ether synthesis in gaseous phase." Collection of Czechoslovak Chemical Communications 55, no. 4 (1990): 1033–37. http://dx.doi.org/10.1135/cccc19901033.

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Kinetics of methyl tert.butyl ether synthesis from methanol and isobutene was measured in gaseous phase at 85 °C and atmospheric pressure on macroreticular ion exchanger catalyst containing strongly acidic functional groups SO3H and on the same catalyst partially neutralized by sodium and iron ions. The form of the best Langmuir-Hinshelwood type kinetic equation suggests absorption of the reactants in the polymer mass causing ìswellingî of it and influencing the accessibility of active sites by the reactants. Neutralization of the catalyst by metal ions suppresses this effect.

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Qiu, Liangwei, Xiaoyang Chen, and Fakai Dong. "Effects of polymers concentration on EHL film-forming in point contacts." Industrial Lubrication and Tribology 73, no. 3 (February 17, 2021): 436–42. http://dx.doi.org/10.1108/ilt-07-2020-0263.

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Purpose This paper aims to experimentally investigate the film-forming capability of base oils containing poly-methacrylate (PMA) and poly-isobutene (PIB), in a point contact under pure rolling. Design/methodology/approach By using the relative light intensity method, the film thickness is calculated from the interferometer images which are captured by multiple-contact optical elastohydrodynamic lubricated test rig. Findings The test results reveal that polymers, both PMA and PIB, have a significant contribution to the film-forming capability of base oils and the film thickness increases with concentration. The forming-film capabilities for PMA and PIB in base oils are similar at low concentration, while PIB gives a higher film thickness than PMA at high concentration. Shear-thinning phenomenon are observed in all polymer-based oils. Originality/value The polymer usually as an additive is added into the low viscosity base oils to improve the properties of lubricant oil. This paper reports the lubricated properties of PMA and PIB with different concentrations in base oils and to evaluate their functional mechanism in a point contact. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2020-0263/

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Kiminami, H., K. Takeuchi, K. Nakamura, Y. Abe, P. Lauwers, W. Dierick, K. Yoshino, and S. Suzuki. "Low Leachable Container System Consisting of a Polymer-Based Syringe with Chlorinated Isoprene Isobutene Rubber Plunger Stopper." PDA Journal of Pharmaceutical Science and Technology 69, no. 6 (November 1, 2015): 713–24. http://dx.doi.org/10.5731/pdajpst.2015.01080.

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Imaizumi, Ryota, Masakazu Furuta, Haruyuki Okamura, and Akikazu Matsumoto. "UV and γ-ray resistance of poly( N -methylmaleimide- alt -isobutene) and poly(diisopropyl fumarate) as transparent polymer films." Radiation Physics and Chemistry 138 (September 2017): 22–28. http://dx.doi.org/10.1016/j.radphyschem.2017.04.018.

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Rezvova, M. A., and E. A. Ovcharenko. "POLYMERIC HEART VALVE PROSTHESES: CONDITION AND PERSPECTIVES." Russian Journal of Transplantology and Artificial Organs 20, no. 2 (June 27, 2018): 100–111. http://dx.doi.org/10.15825/1995-1191-2018-2-100-111.

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The idea of creating a polymer heart valve, which has high strength and biocompatibility, occurs in the 60’s. Since then, many polymer compounds have been investigated, but no solution has been found for this problem. In recent years, in connection with the development of technologies for the synthesis of high-molecular compounds, new polymers have appeared that can solve this problem, as evidenced by a number of publications describing experimental and clinical data. Nevertheless, the search for a polymer for the valve stem of the valvular valve body does not lose its relevance due to the deﬁ ciencies studied and the lack of evidence conﬁ rming the long-term safety of such products. This review presents the ﬁ rst results of a study of polymer heart valves prostheses based on a nanocomposite polymer from polyhedral oligomeric nanoparticles of silicosioxane and polycarbonate urethane polymer POSS-PCU, polystyrene block-isobutylene-block-styrene SIBS, PTFE polytetraﬂ uoroethylene, copolymers and composites based on oleﬁ n polymers series and polyesters, the idea of creating a material with a given three-dimensional microarchitecture that determines the anisotropy and the necessary mechanical properties.

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Rokkonen, Teijo, Pia Willberg-Keyriläinen, Jarmo Ropponen, and Tero Malm. "Foamability of Cellulose Palmitate Using Various Physical Blowing Agents in the Extrusion Process." Polymers 13, no. 15 (July 23, 2021): 2416. http://dx.doi.org/10.3390/polym13152416.

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Polymer foams are widely used in several fields such as thermal insulation, acoustics, automotive, and packaging. The most widely used polymer foams are made of polyurethane, polystyrene, and polyethylene but environmental awareness is boosting interest towards alternative bio-based materials. In this study, the suitability of bio-based thermoplastic cellulose palmitate for extrusion foaming was studied. Isobutane, carbon dioxide (CO2), and nitrogen (N2) were tested as blowing agents in different concentrations. Each of them enabled cellulose palmitate foam formation. Isobutane foams exhibited the lowest density with the largest average cell size and nitrogen foams indicated most uniform cell morphology. The effect of die temperature on foamability was further studied with isobutane (3 wt%) as a blowing agent. Die temperature had a relatively low impact on foam density and the differences were mainly encountered with regard to surface quality and cell size distribution. This study demonstrates that cellulose palmitate can be foamed but to produce foams with greater quality, the material homogeneity needs to be improved and researched further.

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Shakun, A. N., M. L. Fedorova, T. V. Karpenko, and E. V. Demidova. "Isomalk-3 and Isomalk-3R Technologies for Production of Individual Light Paraffins as the Feed for Petrochemical Facilities." World of Oil products the Oil Companies Bulletin 02 (2021): 8–12. http://dx.doi.org/10.32758/2071-5951-2021-0-2-8-12.

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The article discusses the new environmentally friendly catalytic technologies for processing butane cut, developed by SIE Neftehim LLC, giving wide opportunities for involving LPG in production of commercial value-added products. Development of petrochemical industry has created a demand for technologies and catalysts that enhance the economic efficiency of petrochemical products’ manufacturing and expand the feed base of petrochemical facilities without involving primary processing feeds. As the environmentally safe and economically effective solution, SIE Neftehim, LLC offers Isomalk-3 technology to produce maximum amount of isobutane, and Isomalk-3R technology to produce maximum amount of n-butane from isobutane cut. Application of Isomalk-3R technology expands the feed base for ethylene production due to isomerization of isobutane by-product to n-butane. N-butane is a valuable feed for pyrolysis units, providing high yields of ethylene, propylene, and n-butene used for polymer production. In turn, obtaining additional amounts of isobutane is possible due to application of n-butane to isobutane catalytic isomerization technology Isomalk-3. Isobutane cut produced in Isomalk-3 technology is notable for its high purity: the isobutane content may exceed 99 wt.%, it has no sulfur, nitrogen, chlorine, and oxygen impurities. Isobutane is in demand as the feed for production of alkylate, butyl rubber, oxygenates (MTBE and ETBE), isooctane. Isomalk-3 and Isomalk-3R processes do not require injection of chlorinating reagents, and the highly active catalytic system is resistant to poisons and impurities. Isomalk-3 and Isomalk-3R process designs are very similar, which allows integrating two units into one for alternate production of n-butane and isobutane.

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Kresge, Edward N. "SCIENCE AND SERENDIPITY IN POLYOLEFIN ELASTOMER DEVELOPMENT." Rubber Chemistry and Technology 83, no. 3 (September 1, 2010): 227–34. http://dx.doi.org/10.5254/1.3525682.

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Abstract Polyolefin elastomers based on ethylene, propylene, and isobutylene plus other monomers are now widely used in many diverse applications. Major research and development efforts have led to thermoplastic polyolefin soft automobile bumpers, modifiers for lubricating oils, and fast extrusion grades of ethylene–propylene–diene terpolymers. These and other successful commercial innovations depend on the tools of the basic science of structure–property relationships, proper needs assessments, sound engineering, and good management. These tools have been largely provided by my colleagues at ExxonMobil Chemical, customers, and universities and I thank them profoundly. Several historical commercial developments are discussed, including thermoplastic polyolefin elastomers based on ethylene–propylene copolymer–isotactic–polypropylene blends, shear stable viscosity modifiers based on ethylene–propylene copolymers, bimodal molecular weight and compositional distribution EPDM to control rheological characteristics, and diene structure and interchain distribution. In addition, the ongoing research on nanocomposites for tire innerliners based on isobutylene polymers and clay is reviewed. The roles of polymer science, serendipity, and lost opportunity costs on innovation are also discussed.

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BULYCHEV, Nikolay A., and Lev N. RABINSKIY. "SURFACE MODIFICATION OF TITANIUM DIOXIDE NANOPARTICLES WITH ACRYLIC ACID/ISOBUTYLENE COPOLYMER UNDER ULTRASONIC TREATMENT." Periódico Tchê Química 16, no. 32 (August 20, 2019): 338–44. http://dx.doi.org/10.52571/ptq.v16.n32.2019.356_periodico32_pgs_338_344.pdf.

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The influence of the ultrasonic treatment of block copolymer solution on its solid-liquid interface behavior was investigated in detail. The surface modification of titanium dioxide nanoparticles in aqueous dispersions of specially tailor-made periodic acrylic acid/isobutylene copolymer by ultrasonic treatment was studied in order to get new approaches for the creation of hybrid composite materials or polymer coatings. The pigment surface modification by the above copolymer was comparatively investigated regarding conventional adsorption as contrasted to an ultrasonic treatment assisted procedure. The course and efficiency of the polymer adsorption onto the pigment surface were quantified by electrokinetic sonic amplitude measurements. The higher efficiency of the pigment surface coating by the copolymer as achieved by ultrasonic treatment in comparison to conventional adsorption is a consequence of ultrasonically induced pigment surface activation. Two perspective avenues of the utilization of the discovered effects for creation of organic-inorganic composite materials are anticipated: the nanoparticles could first be treated by ultrasound in the presence of polymers and so create a surface modifying coating and the second option is an entrainment of the nanoparticles into the monomer matrix which can be polymerized afterward yielding a polymer with immobilized nanoparticles.

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10

Dias, Anthony J., and Alan A. Galuska. "Curative Migration in Rubber Compounds Containing Brominated Poly(Isobutylene-co-4-Methylstyrene)." Rubber Chemistry and Technology 69, no. 4 (September 1, 1996): 615–27. http://dx.doi.org/10.5254/1.3538389.

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Abstract Blends of elastomers are widely used throughout the rubber industry. Blends are frequently used to get a balance of properties which cannot be achieved through the use of a single elastomer. For example, poly(isobutylene-co-4-bromomethylstyrene) can be blended with highly unsaturated general purpose rubbers to impart unique barrier or dynamic properties and enhanced oxidative stability. The final properties of such a blend are the result of a complex series of compounding, mixing and curing stages. These stages profoundly impact the homogeneity of the mixed components which include: the polymers, the filler, and the curatives. It is important to develop tools to monitor the changes which occur during compounding. This paper details the application of static secondary ion time-of-flight mass spectroscopy (ToF-SSIMS) imaging to simultaneously map polymer phase information with specific chemical information. The paper will highlight the utility of ToF-SSIMS for the study of the chemical and physical changes occurring during elastomer compounding. Blends of poly(isobutylene-co-4-bromomethylstyrene) and general purpose rubbers were compounded with typical cure systems and studied under a variety of mixing conditions.

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Waddell, Walter H., Julie H. Kuhr, and Robert R. Poulter. "Evaluation of Isobutylene-Based Elastomers in a Model Winter Tire Tread." Rubber Chemistry and Technology 76, no. 2 (May 1, 2003): 348–64. http://dx.doi.org/10.5254/1.3547748.

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Abstract The performance of butyl, chlorobutyl, bromobutyl, and brominated isobutylene-co-para-methylstyrene (BIMS) rubbers were evaluated versus a solution-polymerized styrene-butadiene rubber with 20% bound styrene in model winter tire tread formulations containing natural rubber and butadiene rubber. Isobutylene-based elastomer performance was compared in carbon black-filled and silane-coupled silica-filled systems. Based on laboratory dynamic properties predictive of wet and winter traction, and on DIN abrasion index values, BIMS is the elastomer of choice affording increased tangent delta values between 0 °C and −40 °C, and the highest DIN abrasion index values of the isobutylene-based elastomers. Evaluation of BIMS / NR / BR blends in model compounds show its utility as a tread polymer for improving winter performance.

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Pásztói, Balázs, Tobias M. Trötschler, Ákos Szabó, Györgyi Szarka, Benjamin Kerscher, Rolf Mülhaupt, and Béla Iván. "Synthesis of Tosyl- and Nosyl-Ended Polyisobutylenes with High Extent of Functionalities: The Effect of Reaction Conditions." Polymers 12, no. 11 (October 28, 2020): 2504. http://dx.doi.org/10.3390/polym12112504.

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Endfunctional polymers possess significant industrial and scientific importance. Sulfonyl endgroups, such as tosyl and nosyl endfunctionalities, due their ease of substitution are highly desired for a variety of polymer structures. The sulfonylation of hydroxyl-terminated polyisobutylene (PIB-OH), a chemically and thermally stable, biocompatible, fully saturated polymer, with tosyl chloride (TsCl) and nosyl chloride (NsCl) is presented in this study. PIB-OHs derived from commercial exo-olefin-ended PIB (PIBexo-OH) and allyl-terminated polymer made via quasiliving carbocationic polymerization of isobutylene (PIBall-OH) were tosylated and nosylated in the presence of 4-dimethylaminopyridine (DMAP), pyridine and 1-methylimidazole (1-MI) catalysts and triethylamine (TEA). Our systematic investigations revealed that the end product distribution strongly depends on the relative amount of the components, especially that of TEA. While PIBexo-OTs with quantitative endfunctionality is readily formed from PIBexo-OH, its nosylation is not as straightforward. During sulfonylation of PIBall-OH, the formed tosyl and nosyl endgroups are easily substituted with chloride ions, formed in the first step of sulfonylation, leading to chloride termini. We found that decreased amounts of TEA afford the synthesis of PIBall-OTs and PIBall-ONs with higher than 90% endfunctionalities. These sulfonyl-ended PIBs open new ways for utilizing PIB in various fields and in the synthesis of novel PIB-containing macromolecular architectures.

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Ozvald, Adam A., Monika R. Klezcek, Antonio C. Rodrigo, and J. Scott Parent. "ISOBUTYLENE-RICH IMIDAZOLIUM IONOMERS: INFLUENCE OF ION-PAIR DISTRIBUTION AND COUNTER-ANION STRUCTURE." Rubber Chemistry and Technology 91, no. 2 (April 1, 2018): 303–19. http://dx.doi.org/10.5254/rct.18.83700.

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ABSTRACT New chemistry for overcoming the limitations of nonpolar elastomers is detailed, with particular emphasis on improving interfacial adhesion and the intensity of polymer–filler interactions. The chemical modification of brominated poly(isobutylene-co-isoprene) and brominated poly(isobutylene-co-para-methyl styrene) is used to introduce small amounts of imidazolium bromide functionality. Unlike conventional isobutylene-rich elastomers, ionomer derivatives bearing vinylimidazolium bromide groups are peroxide curable. The ultimate cross-link density, along with accompanying thermoset properties, can be tailored by changing the amount and distribution of N-vinylimidazolium and N-butylimidazolium functionality. Moreover, the counteranion can be exchanged from bromide to sulfonate or vinylsulfonate to further optimize adhesive, tensile, and stress relaxation properties. Bromide exchange anionic montmorillonite clay platelets can yield thermoset ionomer nanocomposites with a high degree of reinforcement despite a relatively low filler loading.

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Heublein, G., H. H. Rottmayer, D. Stadermann, and J. Vogel. "Synthese von Poly(isobuten-b-styren-b-isobuten)." Acta Polymerica 38, no. 10 (October 1987): 559–61. http://dx.doi.org/10.1002/actp.1987.010381003.

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Garratt, Shaun, Andrew G. Carr, Gerhard Langstein, and Manfred Bochmann. "Isobutene Polymerization and Isobutene-Isoprene Copolymerization Catalyzed by Cationic Zirconocene Hydride Complexes." Macromolecules 36, no. 12 (June 2003): 4276–87. http://dx.doi.org/10.1021/ma034320p.

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Shiman, Dmitriy I., Vladimir Sayevich, Christian Meerbach, Pavel A. Nikishau, Irina V. Vasilenko, Nikolai Gaponik, Sergei V. Kostjuk, and Vladimir Lesnyak. "Robust Polymer Matrix Based on Isobutylene (Co)polymers for Efficient Encapsulation of Colloidal Semiconductor Nanocrystals." ACS Applied Nano Materials 2, no. 2 (January 29, 2019): 956–63. http://dx.doi.org/10.1021/acsanm.8b02262.

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Sukhareva, K. V., I. A. Mikhailov, and E. E. Mastalygina. "Properties of Elastomeric Adhesive Composition Based on Chlorinated Isobutylene Isoprene Rubber Obtained by Mechanochemical Halide Modification." Solid State Phenomena 265 (September 2017): 308–12. http://dx.doi.org/10.4028/www.scientific.net/ssp.265.308.

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This paper is devoted to the main characteristics of adhesive composites based on chlorinated isobutylene isoprene rubber with different content of chlorine obtained by the novel technology of mechanochemical halide modification of rubbers based on mechanical initiating of the combination reaction of halide in liquid phase. In the work the basic properties characterizing adhesive, protective and paint coatings have been studied with the main focus on dependence of the materials properties on chlorine content in chlorinated isobutylene isoprene rubber used as polymer basis of adhesive compositions under investigation. Based on the study results of the technological properties of elastomeric adhesive composition, the optimal adhesive composition has been recommended.

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Lim, Goy Teck, Elizabeth A. Foreman-Orlowski, Sara E. Porosky, Paul Pavka, Judit E. Puskas, Christian Götz, and Volker Altstädt. "Novel Polyisobutylene-Based Biocompatible TPE Nanocomposites." Rubber Chemistry and Technology 82, no. 4 (September 1, 2009): 461–72. http://dx.doi.org/10.5254/1.3548258.

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Abstract The tensile and thermal properties of linear poly(styrene-b-isobutylene-b-styrene) (L_SIBS) and styrenic copolymers with a dendritic polyisobutylene core (D_SIBS) filled with 10 – 30 wt% of organophilic montmorillonite nanoclays (Cloisite(®)-20A) via solution blending were investigated. D_SIBS polymers were successfully reinforced by the clays without additional compatibilizers to show increase in both modulus and ultimate tensile strength. The clay platelets were well dispersed in the polymer matrix as determined by transmission electron microscopy (TEM). However, L_SIBS composites displayed decreasing tensile strength with increasing clay loading. TEM found clay agglomerates in L_SIBS composites that can act as “hotspots” for premature failure of the material. D_SIBSs loaded with 60 phr (37.5 wt%) carbon black (N234) also showed significant reinforcement. Interestingly, a D_SIBS with 17 wt% hard phase content reinforced with 60 phr carbon black exhibited an increase in the glass transition temperature of the hard phase from 116 °C to 126 °C. This will make steam sterilization of the material possible for biomedical applications.

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Saiwari, S., W. K. Dierkes, and J. W. M. Noordermeer. "COMPARATIVE INVESTIGATION OF THE DEVULCANIZATION PARAMETERS OF TIRE RUBBERS." Rubber Chemistry and Technology 87, no. 1 (March 1, 2014): 31–42. http://dx.doi.org/10.5254/rct.13.87933.

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ABSTRACT The optimal process conditions for a high ratio of devulcanization to polymer degradation have been investigated for tire rubbers: styrene–butadiene rubber (SBR), butadiene rubber (BR), natural rubber (NR), and chloro-isobutylene–isoprene rubber (CIIR). These polymers all show their own particular breakdown characteristics. The temperature dependence of the breakdown mechanism was investigated by measuring sol fractions and cross-link densities. For SBR and BR, the highest reduction in cross-link density was found at a temperature of 220 °C, together with a moderate increase in sol content. According to the Horikx theory, which correlates sol fraction and a decrease in cross-link density, this is the result of a high degree of cross-link scission. Higher process temperatures result in a lower decrease in cross-link density due to recombination of active chain fragments. NR and CIIR show different behavior. Breakdown of NR in this temperature range results in an almost complete destruction of the polymer network; cross-link density is reduced to almost zero, and the sol fraction is close to 100%. The same result is found for CIIR at higher temperatures. Although different rubbers react via other devulcanization mechanisms, the best devulcanization conditions for whole passenger car tire material are optimized.

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Sangalov, Yu A., Yu Ya Nel'kenbaum, I. K. Prokof'ev, R. A. Sadykov, and N. M. Shishlov. "Compatibility of isobutylene polymers with polysiloxanes." Polymer Science U.S.S.R. 29, no. 3 (January 1987): 651–57. http://dx.doi.org/10.1016/0032-3950(87)90276-0.

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Kaszas, Gabor, and Binh Tran. "Synthesis, Bromination and Cure of Isobutylene/Isoprene/P-Methylstyrene and Isobutylene/Isoprene/Styrene Terpolymers." Rubber Chemistry and Technology 75, no. 1 (March 1, 2002): 155–69. http://dx.doi.org/10.5254/1.3547667.

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Abstract High molecular weight isobutylene/isoprene/p-methylstyrene and isobutylene/isoprene/styrene terpolymers containing up to 10.6 mol% p-methylstyrene and 3.6 mol% styrene were synthesized using “H2O”/AlCl3 as an initiator/coinitiator system in methylchloride at -95 °C. p-Methylstyrene was found to be uniformly distributed in the chains due to its similar reactivity to isobutylene. In contrast, styrene had a lower reactivity than isobutylene or even isoprene, resulting in low conversion of the styrene monomer. The reactivity ratios obtained were in good agreement with the published values. Up to about 3 mol% styrenic monomer content, the Tg of the terpolymers showed no significant increase. The isoprene units of the terpolymers were brominated by the conventional bromination technique. During bromination, some of the aromatic rings also underwent bromination. The extent of this reaction was found to be much lower in the case of p-methylstyrene than in the case of styrene. The brominated terpolymers were cured using ZnO. The brominated terpolymers displayed much faster cure, higher maximum torque and modulus at the same brominated isoprene concentration than brominated copolymers of isobutylene and isoprene, indicating that the aromatic rings participate in the cure. The brominated terpolymers showed an increased resistance to hot air aging, compared to brominated polymers containing no styrenic termonomer.

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Kasalo, Ruzica, and Markus Busch. "Quantitative NMR Spectroscopy and Determination of Polymer Microstructure of Ethylene-Styrene and Ethylene-Isobutylene Co -Polymers." Macromolecular Symposia 324, no. 1 (February 2013): 78–81. http://dx.doi.org/10.1002/masy.201200070.

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Svec, F., J. M. J. Fréchet, and I. Duvdevani. "Testing of Compositional Distribution in Brominated Isobutylene Elastomers." Rubber Chemistry and Technology 77, no. 1 (March 1, 2004): 78–89. http://dx.doi.org/10.5254/1.3547815.

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Abstract A method based on high-performance liquid chromatography (HPLC) method has been developed for the characterization of the compositional distribution of brominated poly(isobutylene-co-4-methylstyrene) and poly(isobutylene-co-isoprene). The desired separations in normal-phase chromatographic mode could only be achieved by using columns packed with specifically developed 10 and 3 µm porous monodisperse poly(2,3-dihydroxypropyl methacrylate-co-ethylene dimethacrylate) beads that have a homogeneous coverage of aliphatic hydroxyl groups. Linear gradients of tetrahydrofuran in hexane and dichloromethane in heptane were used respectively as the mobile phases for the selective elution of brominated poly(isobutylene-co-4-methylstyrenes) and brominated poly(isobutylene-co-isoprenes). In-column solvo-thermal treatment of the stationary phase further improved both selectivity and retention and enabled the easy detection and detailed quantification of differences in bromine content well below 1 mol %.

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Binder, Wolfgang H., Steffen Kurzhals, Bhanuprathap Pulamagatta, Ulrich Decker, Gjanan Manohar Pawar, Dongren Wang, Christa Kühnel, and Michael R. Buchmeiser. "Homologous Poly(isobutylene)s: Poly(isobutylene)/High-Density Poly(ethylene) Hybrid Polymers." Macromolecules 41, no. 22 (November 25, 2008): 8405–12. http://dx.doi.org/10.1021/ma801465r.

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Rodgers, Brendan, Scott Solis, Nitin Tambe, and Bharat B. Sharma. "Alkylphenol Disulfide Polymer Accelerators and the Vulcanization of Isobutylene Based Elastomers." Rubber Chemistry and Technology 81, no. 4 (September 1, 2008): 600–624. http://dx.doi.org/10.5254/1.3548222.

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Abstract Vulcanization of isobutylene/isoprene copolymer (butyl rubber) using sulfur and organic accelerators is facilitated by the presence of the carbon-carbon double bond in the copolymer isoprenyl unit. The low number of unsaturated monomer units, usually in the order of 2%, has traditionally necessitated use of ultra-fast accelerators such as tetramethyl thiuram disulfide (TMTD) or zinc dimethyldithiocarbamate (ZMDC). Use of such accelerators can result in formation of nitrosamines which may be undesirable. There are a number of alternatives to thiuram and dithiocarbamate cure systems such as use of xanthates and phosphate based accelerators. Alkylphenol disulfide based accelerators also enable attainment of favorable properties when used in butyl and halobutyl compounds. Use of alkylphenol disulfide accelerators in butyl rubber compounds can allow improvement in reversion resistance, adhesion to natural rubber tire casing compounds, and aged property retention. In bromobutyl compounds containing alkylphenol disulfide accelerators in binary (two accelerators) or tertiary (three accelerators) cure systems, adjustment in cure rate to meet specific requirements and aged property retention is possible. This, fifth in a series of studies on the vulcanization of isobutylene elastomers, explores the use of alkylphenol disulfide cure systems for vulcanization of both butyl and bromobutyl rubbers and is intended to provide a starting point for further development work.

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Puskas, Judit E. "RUBBER CITY GIRL: THE PATH TO THE GOODYEAR MEDAL." Rubber Chemistry and Technology 91, no. 1 (January 1, 2018): 1–26. http://dx.doi.org/10.5254/rct.17.82588.

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ABSTRACT An overview of my 40-year career will be provided, spanning both industry and academe, and two continents. During my industrial years at LANXESS (formerly the Rubber Division of Bayer), I solved long-standing (10-yr) major manufacturing problems related to Taktene-55 and developed on-line and off-line process control tools that are still in operation. I also developed new technologies (bimodal butyl, one-step halobutyl, branched butyl, liquid carbon dioxide process) that resulted in patents. After transferring to academe, I continued the development of new polyisobutylene-based materials. I have held the Bayer (LANXESS) Industrial Research Chair for 12 yr, working closely with the rubber industry. My most important accomplishments include developing advanced elastomers and thermoplastic elastomers for health care, enzyme-catalyzed polymer functionalization, a “green” synthesis of disulfide polymers and gels, and research into natural rubber biosynthesis. Poly(styrene-isobutylene-polystyrene) is used in a Food and Drug Administration–approved drug-eluting stent, implanted in more than six million patients, saving lives. The recently patented poly(alloocimene-isobutylene-alloocimene) is also a potential biomaterial and also a potential halogen-free halobutyl rubber. I will also discuss my adventure of a field experiment at a Brazilian Hevea plantation to verify our laboratory discovery that the rubber content of Hevea latex can be increased by 20–50% using a special method of tapping. My goal now is creating safer breast implants with cancer-fighting and healing properties. I am proud that the Rubber World trade journal listed me among the 125 inventors that influenced rubber technology in a profound way. I thank my family, Professor Joseph P. Kennedy, and Dr. Adel Halasa for their mentorship and support.

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Wang, Wentao, Xin Ji, Hunter Burns, and Hedi Mattoussi. "A multi-coordinating polymer ligand optimized for the functionalization of metallic nanocrystals and nanorods." Faraday Discussions 191 (2016): 481–94. http://dx.doi.org/10.1039/c6fd00056h.

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We report the design and use of a multi-coordinating polymer ligand that is ideally suited for functionalizing gold nanoparticles and nanorods, and promoting their steric stabilization in buffer media. The ligand is prepared via a one-step nucleophilic addition reaction between poly(isobutylene-alt-maleic anhydride) and amine-modified anchoring groups and hydrophilic moieties. Surface functionalization of gold nanoparticles and nanorods with this polymer yields nanocrystals that exhibit excellent long-term colloidal stability over a broad range of conditions, including pH changes and in growth media, as verified using dynamic light scattering measurements combined with agarose gel electrophoresis. This polymer coating can also prevent the formation of protein corona. These features bode well for use in biological applications where small size, reduced nonspecific interactions and colloidal stability are highly desired. Furthermore, this design can be easily expanded to functionalize a variety of other inorganic nanocrystals.

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Rabeony, M., R. T. Garner, C. W. Elspass, D. G. Peiffer, M. Lin, K. O. McElrath, J. A. Dias, and J. P. Cross. "Phase Behavior of Brominated Poly(Isobutylene-co-4-Methylstyrene)/General Purpose Rubber Blends." Rubber Chemistry and Technology 72, no. 5 (November 1, 1999): 910–17. http://dx.doi.org/10.5254/1.3538841.

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Abstract The thermodynamic interaction and phase behavior of elastomeric blends, specifically brominated poly(isobutylene-co-4-methylstyrene) and a general purpose rubber, polybutadiene, have been examined using small-angle neutron scattering (SANS) and cloud points measurements. The low molecular weight equivalent of each segment was used to produce a single phase blend from which the Flory-Huggins interaction parameter (λ) was extracted. The results were analyzed using the random copolymer formalism. The results show that the “repulsive” interaction between the isobutylene and 4-methylstyrene monomer units enhances the compatibility of brominated poly(isobutylene-co-4-methylstyrene) with polybutadiene. A maximum in compatibility occurs at approximately 50 mol % 4-methylstyrene. This fundamental information is essential for the determination of the phase behavior of these materials, and their regions of miscibility/immiscibility. In addition, this information can be used to calculate the optimum copolymer composition for this scientifically interesting and technologically important blend system.

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29

Hong, Seong-Uk, J. Larry Duda, and David C. Venerus. "Diffusion of organic solvents in isobutylene-based polymers." Korean Journal of Chemical Engineering 13, no. 3 (May 1996): 255–60. http://dx.doi.org/10.1007/bf02705947.

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30

Carr, Andrew G., David M. Dawson, and Manfred Bochmann. "The [Zr(N{SiMe3}2)3]+ cation as a novel initiator for carbocationic isobutene homo- and isobutene/isoprene co-polymerisations." Macromolecular Rapid Communications 19, no. 4 (April 1, 1998): 205–7. http://dx.doi.org/10.1002/(sici)1521-3927(19980401)19:4<205::aid-marc205>3.0.co;2-7.

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31

Carr, Andrew G., David M. Dawson, and Manfred Bochmann. "The [Zr(N{SiMe3}2)3] cation as a novel initiator for carbocationic isobutene homo- and isobutene/isoprene co-polymerisations." Macromolecular Rapid Communications 19, no. 4 (April 1998): 205–7. http://dx.doi.org/10.1002/marc.1998.030190409.

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32

Ulitin, N. V., K. A. Tereshchenco, D. A. Shiyan, and G. E. Zaikov. "CATIONIC COPOLYMERIZATION OF ISOBUTYLENE WITH ISOPRENE: KINETICS OF THE PROCESS AND DETERMINATION OF KINETIC CONSTANTS." Rubber Chemistry and Technology 88, no. 4 (December 1, 2015): 574–83. http://dx.doi.org/10.5254/rct.15.84889.

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ABSTRACT A theoretical description has been developed of the kinetics of isobutylene with isoprene (IIR) cationic polymerization in the environment of methyl chloride on aluminum trichloride as the catalyst. Based on experimental data on the kinetics of copolymerization (isobutylene conversion curve) and the molecular weight characteristics of the copolymer of IIR, kinetic constants for the process were found. Adequacy of the developed theoretical description of the kinetics of the IIR copolymerization process was confirmed by comparing the experimental molecular-weight characteristics calculated by this description, independent characteristics, and IIR unsaturation.

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33

Tse, Calvin K. W., Anca Penciu, Paula J. McInenly, Kainthan R. Kumar, Mark J. Drewitt, and Michael C. Baird. "Isobutene homo- and isobutene-isoprene copolymerization initiated by protic initiators associated with a series of novel, weakly coordinating counteranions." European Polymer Journal 40, no. 12 (December 2004): 2653–57. http://dx.doi.org/10.1016/j.eurpolymj.2004.07.019.

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34

Maier, R. D., M. Kopf, D. Mäder, F. Koopmann, H. Frey, and J. Kressler. "Thermodynamics of polymer blends of poly(isobutylene) and poly(dimethylsilylenemethylene)." Acta Polymerica 49, no. 7 (July 1998): 356–62. http://dx.doi.org/10.1002/(sici)1521-4044(199807)49:7<356::aid-apol356>3.0.co;2-m.

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35

Wang, Wentao, Fadi Aldeek, Xin Ji, Birong Zeng, and Hedi Mattoussi. "A multifunctional amphiphilic polymer as a platform for surface-functionalizing metallic and other inorganic nanostructures." Faraday Discuss. 175 (2014): 137–51. http://dx.doi.org/10.1039/c4fd00154k.

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We designed a new set of polymer ligands that combine multiple metal-coordinating groups and short polyethylene glycol (PEG) moieties in the same structure. The ligand design relies on the controlled grafting of a large number of amine-terminated histamines and PEG short chains onto a poly(isobutylene-alt-maleic anhydride) backbone,viaa one-step nucleophilic addition reaction. This addition reaction is highly efficient, can be carried out in organic media and does not require additional reagents. We show that when imidazole groups are used the resulting polymer ligand can strongly ligate onto metal nanostructures such as nanoparticles (NPs) and nanorods (NRs) made of gold cores. The resulting polymer-coated NPs and NRs exhibit good colloidal stability to pH changes and added electrolytes. This constitutes a departure from the use of thiol-based ligands to coordinate on Au surfaces. The present chemical approach also opens up additional opportunities for designing hydrophilic and reactive platforms where the polymer coating can be adjusted to various metal and metal oxide surfaces by simply modifying or combining the addition reaction with other metal coordinating groups. These could include iron oxide NPs and semiconductor QDs. These polymer-capped NPs and NRs can be used to develop biologically-active platforms with potential use for drug delivery and sensing.

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Maenz, Karsten, and Dietmar Stadermann. "Comb-like polymers from macromonomers based on low-molecular-weight poly(isobutene)s." Die Angewandte Makromolekulare Chemie 258, no. 1 (August 1, 1998): 69–73. http://dx.doi.org/10.1002/(sici)1522-9505(19980801)258:1<69::aid-apmc69>3.0.co;2-g.

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Alwan, Adil A., and Ali J. Mohammad. "MATHEMATICAL MODEL TO INVESTIGATE THE DRAG REDUCTION OF KEROSENE WITH POLYMER UNDER TURBULENT FLOW." IRAQI JOURNAL FOR MECHANICAL AND MATERIALS ENGINEERING 18, no. 4 (January 5, 2019): 577–88. http://dx.doi.org/10.32852/iqjfmme.v18i4.222.

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This paper present a mathematical study on drag reduction by polymer additive suchas poly isobutylene (PIB) with kerosene in turbulent pipe flow by using computational fluiddynamic commercial package program (COMSOL 4.4) solution. Theoretically thecomputational study was used to calculate the pressure drop in two dimensions geometricmodel with 6m length and 80 mm width as a diameter of the pipe, Geometric shape has beendrawing by tools of the program windows, and to simulated the flow region mathematicallythe flow region is divide into very small parts (mesh generation). The model that used in themathematical modelling method was (k-?( mathematical turbulent model to study theinternal pipe flow properties. The continuity and momentum equations and two k-? modelequations have been solved by the program to obtain the theoretical results. There variablesthat used in the theoretical study were effective density, effective viscosity, inlet velocity,and outlet pressure. The boundary condition was inlet and outlet velocity, temperature, andpressure of flow, and the velocity (u=0) at the pipe wall. The theoretical calculations showthat the velocity and drag reduction percentage increases with polymer concentration andvolume flow rate increasing where maximum DR% is 15.8% at volume flow rate 500 ??minwith polymer concentration 100 ppm, pressure drop decreases with polymer concentrationincreasing. Friction factor decreases with polymer concentration increased, also shear stressdecrease with polymer concentration increasing.

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Frasca, Daniele, Dietmar Schulze, Volker Wachtendorf, Michael Morys, and Bernhard Schartel. "Multilayer graphene/chlorine-isobutene-isoprene rubber nanocomposites: the effect of dispersion." Polymers for Advanced Technologies 27, no. 7 (January 5, 2016): 872–81. http://dx.doi.org/10.1002/pat.3740.

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39

Nuyken, Oskar, and Mario Vierle. "Polymerization of isobutene: past research and modern trends." Designed Monomers and Polymers 8, no. 2 (January 2005): 91–105. http://dx.doi.org/10.1163/1568555053603233.

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40

Jiang, Yang, Zhen Zhang, Shihui Li, and Dongmei Cui. "Isobutene (co)polymerization initiated by rare-earth metal cationic catalysts." Polymer 187 (January 2020): 122105. http://dx.doi.org/10.1016/j.polymer.2019.122105.

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41

Ruiz-Colón, Eduardo, and David Suleiman. "Synthesis and Characterization of Phosphonated Graphene Oxide and Sulfonated Poly(styrene-isobutylene-styrene) Composite Membranes." MRS Advances 3, no. 47-48 (2018): 2905–12. http://dx.doi.org/10.1557/adv.2018.438.

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AbstractGraphene oxide (GO) and its phosphonated analogue (pGO) have been incorporated into sulfonated poly(styrene-isobutylene-styrene) (SO3H SIBS) to generate membranes with enhanced water retention. The polymer nanocomposite membranes (PNMs) were prepared per SIBS sulfonation level (i.e., 38, 61, and 90 mole %), filler type (i.e., GO and pGO) and filler loading (i.e., 0.1, 0.5 and 1.0 wt.%). FT-IR and TGA confirmed the functionalization and incorporation of the fillers into SO3H SIBS. No significant changes were observed in the thermal stability or FTIR spectra of the PNMs after addition of the fillers. Dissimilar behaviors were observed for the water absorption capabilities (i.e., swelling ratio and water uptake) after incorporation of the fillers. The nanofillers enhanced the water absorption of the sulfonated polymer, possibly due to interconnections between the ionic groups. Therefore, the PNMs could not only potentially function as proton exchange membranes (PEMs) for several applications such as direct methanol fuel cells (DMFCs).

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42

Bulychev, N., E. Kisterev, H. Reimann, C. Schaller, and C. D. Eisenbach. "Ultrasonic Treatment Enhanced Surface Modification of Titanium Oxide by Tailor-Made Surface-Active Polymers." Eurasian Chemico-Technological Journal 11, no. 2 (April 6, 2016): 121. http://dx.doi.org/10.18321/ectj305.

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The surface modification of titanium dioxide in aqueous dispersions of specially tailor-made periodic acrylic acid/isobutylene copolymers, poly(acrylic acid)/polystyrene graft copolymers, and hydrophobically modified polyethyleneoxide urethane (HEUR) by ultrasonic treatment was studied. The pigment surface modification by the above copolymers was comparatively investigated regarding conventional adsorption as contrasted to an ultrasonic treatment assisted procedure. The course and efficiency of the polymer adsorpption onto the pigment surface was quantified by electrokinetic sonic amplitude measurements. The higher efficiency of the pigment surface coating by the copolymers as achieved by ultrasonic treatment varies with the copolymer architecture and is a consequence of ultrasonically induced pigment surface activation.

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43

Tse, Mun F., A. J. Dias, and H.-C. Wang. "Characterization and Physical Properties of New Isobutylene-Based Graft Copolymers." Rubber Chemistry and Technology 71, no. 4 (September 1, 1998): 803–19. http://dx.doi.org/10.5254/1.3538506.

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Abstract A number of isobutylene-based graft copolymers with different compositions are compared to several commercial thermoplastic block copolymers, such as SIS, SBS and SEBS, in terms of morphology and viscoelasticity. The backbone of these graft copolymers is a terpolymer (BIMS) of isobutylene, p-methylstyrene and p-bromomethylstyrene, and the side chains are either polystyrene or poly(2,6-dimethyl-1,4-phenylene ether). Graft copolymer synthesis, statistics of graft formation, and stress-strain properties are described. Overall, these graft copolymers exhibit unique shear dependent viscosity effects, such as rapid thickening (quick setting) at low shear and lower viscosity (better processability) at high shear, compared to linear triblock copolymers. The rheological behavior of these graft copolymers could be a key advantage for high-shear calendering, extrusion, hot-melt spraying, and injection molding.

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44

Heublein, G., G. Knöppel, and I. Winnefeld. "Zur kationischen Copolymerisation von Cyclopentadien und Isobuten." Acta Polymerica 38, no. 1 (January 1987): 10–15. http://dx.doi.org/10.1002/actp.1987.010380103.

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45

Touchard, Virginie, Roger Spitz, Christophe Boisson, and Marie-France Llauro. "Highly Active Yttrium and Lanthanide Catalysts for Polymerization of Isobutene." Macromolecular Rapid Communications 25, no. 23 (December 3, 2004): 1953–57. http://dx.doi.org/10.1002/marc.200400419.

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46

McNeish, Joanne R., J. Scott Parent, and Ralph A. Whitney. "Halogenated poly(isobutylene-co-isoprene): influence of halogen leaving-group and polymer microstructure on chemical reactivity." Canadian Journal of Chemistry 91, no. 6 (June 2013): 420–27. http://dx.doi.org/10.1139/cjc-2013-0068.

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Brominated (BIIR) and chlorinated (CIIR) poly(isobutylene-co-isoprene) are commercially available materials commonly known as halobutyl rubbers. The effect of leaving-group ability on the reactivity of halogenated poly(isobutylene-co-isoprene) was studied to place iodobutyl rubber reactivity into context with these materials. The effect of microstructure on reactivity of existing commercial materials was studied through comparison to that of polymers containing rearranged halomethyl (r-CIIR, r-BIIR, and r-IIIR) microstructure (prepared from as-received BIIR). The effect of leaving group on both thermal stability and reactivity towards nucleophilic substitution with acetate, N-butylimidazole, and sulfur was examined. The material containing the iodomethyl microstructure (r-IIIR) readily underwent nucleophilic substitution at low temperatures; however, it was extremely sensitive towards dehydrohalogenation at temperatures above 65 °C. At temperatures between 100 and 135 °C, the material containing the bromomethyl microstructure (r-BIIR) demonstrated the greatest balance between reactivity toward nucleophilic substitution and elimination through dehydrohalogenation. Exceptional thermal stability at temperatures up to 190 °C was displayed by the material containing the chloromethyl microstructure (r-CIIR); however, its reactivity towards nucleophiles was variable and nucleophile dependent. Sulfur vulcanization studies showed a clear effect of microstructure on the ability to cure with sulfur. While commercial chlorobutyl rubber has no ability to cure with sulfur alone, when rearranged to its chloromethyl microstructure (r-CIIR), curing occurs readily. Both commercial (BIIR) and rearranged (r-BIIR) bromobutyl rubber readily vulcanize in the presence of sulfur; however, BIIR cures to a greater extent.

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Li, Xiaoning, Yibo Wu, Jinghan Zhang, Shuxin Li, Min Zhang, Dan Yang, Hao Wang, Yuwei Shang, Wenli Guo, and Penghua Yan. "Synthesis of highly reactive polyisobutylenesviacationic polymerization in ionic liquids: characteristics and mechanism." Polymer Chemistry 10, no. 2 (2019): 201–8. http://dx.doi.org/10.1039/c8py01141a.

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48

Jacob, Sunny, Istvan Majoros, and Joseph P. Kennedy. "Novel Thermoplastic Elastomers: Star-Blocks Consisting of Eight Poly(Styrene-b-Isobutylene) Arms Radiating from a Calix[8]Arene Core." Rubber Chemistry and Technology 71, no. 4 (September 1, 1998): 708–21. http://dx.doi.org/10.5254/1.3538499.

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Abstract The first synthesis by a core-first strategy of novel star-block copolymers consisting of eight poly(styrene-b-isobutylene) (PSt-b-PIB) arms radiating from a calix[8]arene core is described. An octafunctional methoxy calix[8]arene derivative was used to initiate the living polymerization of isobutylene (IB) to desirable molecular weights, then styrene (St) was added to obtain the sought star-blocks. Molecular weights and PSt contents were determined by triple-detector GPC and 1H NMR spectroscopy. Star-block thermoplastic elastomers containing 17–32% PSt showed high strength and elongation (up to ∼26 MPa and >500%) and relatively low melt viscosities. The mechanical and rheological properties of these star-blocks are superior to those of linear PSt-b-PIB-b-PSt triblocks. PIB-based thermoplastic elastomers may be of use as novel biomaterials.

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Ivanova, S. R., I. Yu Ponedel'kina, T. V. Romanko, M. M. Karpasas, and K. S. Minsker. "Thermocatalytic degradation of isobutylene polymers in presence of magnesium chlorides." Polymer Science U.S.S.R. 28, no. 6 (January 1986): 1356–60. http://dx.doi.org/10.1016/0032-3950(86)90126-7.

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50

Fréchet, J. M. J., R. Bielski, H.-C. Wang, J. V. Fusco, and K. W. Powers. "Electrophilic Addition of Brominated Poly(Isobutylene-co-4-Methylstyrene) to Olefins Catalyzed by Zinc Salts: A Model Study." Rubber Chemistry and Technology 66, no. 1 (March 1, 1993): 98–108. http://dx.doi.org/10.5254/1.3538303.

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Abstract The chemical reactivity of a new elastomer based on brominated poly(isobutylene-co-4-methylstyrene) in electrophilic additions to olefins has been investigated using model compounds as well as appropriate polymers. The reactions catalyzed by zinc salts are influenced by the solubility as well as the composition of the catalyst. While the reactivity of zinc bromide is limited by its low solubility in nonpolar medium, zinc oxide and zinc stearate can afford excellent results once an induction period has elapsed. The induction period likely corresponds to the formation of more reactive zinc based moieties through interchange reactions with the benzylic bromide groups. The mechanism of the addition process involves initial formation of carbocationic complexes with the zinc salts, followed by addition to the double bonds of the olefins. The products resulting from these additions have been characterized by NMR as well as gas chromatography-mass spectrometry. A comparison of potential crosslinking processes involving olefin addition or electrophilic aromatic substitution reactions shows that the former process is preferred. The findings of this study are directly applicable to the co-curing of elastomers based on brominated poly-(isobutylene-co-4-methylstyrene) with polyolefins.

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Journal articles on the topic 'Isobutene polymer'

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