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Journal articles on the topic 'Gel permeation chromatography (GPC)'

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Published: 4 June 2021
Last updated: 1 February 2022

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1

Weisskopf, Klaus. "Characterization of polyethylene terephthalate by gel permeation chromatography (GPC)." Journal of Polymer Science Part A: Polymer Chemistry 26, no. 7 (July 1988): 1919–35. http://dx.doi.org/10.1002/pola.1988.080260718.

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2

Milana, M. R., M. Denaro, L. Arrivabene, A. Maggio, and L. Gramiccioni. "Gel permeation chromatography (GPC) of repeatedly extruded polyethylene terephthalate (PET)∗." Food Additives and Contaminants 15, no. 3 (April 1998): 355–61. http://dx.doi.org/10.1080/02652039809374651.

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3

Ouano, A. C. "Gel permeation chromatography VII. Molecular weight detection of gpc effluents." Journal of Polymer Science: Polymer Symposia 43, no. 1 (March 8, 2007): 299–310. http://dx.doi.org/10.1002/polc.5070430126.

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4

Daft, James, Marvin Hopper, Darrell Hensley, and Ronald Sisk. "A Displacement Pump Procedure to Load Extracts for Automated Gel Permeation Chromatography." Journal of AOAC INTERNATIONAL 73, no. 6 (November 1, 1990): 992–94. http://dx.doi.org/10.1093/jaoac/73.6.992.

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Abstract Automated gel permeation chromatography (GPC) effectively separates lipids from pesticides In sample extracts that contain fat. Using a large syringe to load sample extracts manually onto GPC models having 5 mL holding loops is awkward, slow, and potentially hazardous. Loading with a small-volume displacement pump, however, Is convenient and fast (ca 1 loop every 20 s). And more Importantly, the analyst is not exposed to toxic organic vapors because the loading pump and Its connecting lines do not leak in the way that a syringe does.
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5

Gu, Qiang, Xiaojuan Yi, Jinling Shen, Jing Shi, Yijun Liu, and Jingdong Shao. "A highly automated method for simultaneous determination of sterols, erythrodiol and uvaol in olive oils." Analytical Methods 8, no. 20 (2016): 4022–27. http://dx.doi.org/10.1039/c6ay00357e.

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In this work, we presented a highly automated method for the simultaneous analysis of sterols, erythrodiol and uvaol in olive oils with the use of gel permeation chromatography (GPC), an automatic solvent evaporator and LC-MS.
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6

Furusawa, Naoto, Kunio Okazaki, Sachiko Iriguchi, Hidemasa Yamaguchi, and Minoru Saitoh. "Gel Permeation and Florisil Chromatographic Cleanup and Gas Chromatographic Determination of Organochlorine Pesticides in Eggs." Journal of AOAC INTERNATIONAL 81, no. 5 (September 1, 1998): 1033–36. http://dx.doi.org/10.1093/jaoac/81.5.1033.

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Abstract Cleanup of residual organochlorine pesticides (OCPs; α-, β-, γ-, and δ-BHC; aldrin; dieldrin; p,p′-DDE; o,p′-DDT; p,p′-DDD; and p,p′-DUX) in eggs by gel permeation chromatography (GPC) and Florisil minicolumn chromatography is described. Ten OCPs in purified extract are determined by gas chromatography with electron capture detection. The lipids extracted from whole egg are cleaned up first by GPC with an Envirogel column and an ethyl acetate-cychlohexane (1 + 1, v/v) mobile phase and then by Florisil minicolumn chromatography with 15% (v/v) diethyl ether-hexane eluant. Cleanup is highly efficient. Average recoveries of 10 spiked OCPs (0.0025-0.0125 ppm) ranged from 81 to 101%, with coefficients of variation between 1 and 14%. The detection limit was 0.001 ppm for the 10 OCPs
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7

Shen, Teng Fei, and Ying Juan Sun. "Preparation and Characterization of Novel Bipolar Copolymers Based on Quinoline Aluminum and Carbazole." Advanced Materials Research 785-786 (September 2013): 656–59. http://dx.doi.org/10.4028/www.scientific.net/amr.785-786.656.

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In this work, a series of novel bipolar copolymers containing 8-hydroxyquinoline aluminum (Alq3) and carbazole had been synthesized by copolymerization of a novel Alq3 complex monomer and N-vinylcarbazole (NVK), and characterized by Fourier transform infrared spectra (FTIR), gel permeation chromatography (GPC) and differential scanning calorimetry (DSC).
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8

Maziarz, E. Peter, and X. Michael Liu. "A Modified Thermal Deposition Unit for Gel-Permeation Chromatography with Matrix-Assisted Laser Desorption/Ionization and Electrospray Ionization Time-of-Flight Analysis." European Journal of Mass Spectrometry 8, no. 5 (October 2002): 397–401. http://dx.doi.org/10.1255/ejms.500.

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We describe a modified commercially available thermal deposition unit that incorporates a post-column mixing cell for gel-permeation chromatography (GPC) effluent and matrix solution prior to continuous deposition onto a matrix-assisted laser desorption/ionization (MALDI) sample target. This modification overcomes the shortcomings of using a prefabricated matrix foil. This GPC MALDI method with time-of-flight (ToF) mass spectrometry is demonstrated by the analysis of a poly(dimethylsiloxane) (PDMS) sample used in the production of implantable device materials.
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9

Shen, Jiang Nan, Yun Fei Ye, Gan Ning Zeng, and Jun Hong Qiu. "Preparation and Characterization of PMMA-b-PDMAEMA/Polysulfone Composite Membranes by RAFT Polymerization and their Permeation Performance of Carbon Dioxide." Advanced Materials Research 284-286 (July 2011): 1717–23. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.1717.

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PMMA-b-PDMAEMA/polysulfone composite membranes for CO2separation was prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization techniques. The chemical composition and structure of the polymers were characterized by Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR), and molecular weight and its distribution were measured by Gel permeation chromatography (GPC). CO2permeation performance of the PMMA-b-PDMAEMA/ polysulfone composite membranes was test. The results showed that the resulted composited membrane posses good permeation performance for CO2.
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10

DOBKOWSKI, ZBIGNIEW. "A procedure for molecular characteristics of polymers by gel permeation chromatography (GPC)." Polimery 37, no. 04 (April 1992): 146–51. http://dx.doi.org/10.14314/polimery.1992.146.

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11

Hopper, Marvin L., and Kenneth R. Griffitt. "Evaluation of an Automated Gel Permeation Cleanup and Evaluation System for Determining Pesticide Residues in Fatty Samples." Journal of AOAC INTERNATIONAL 70, no. 4 (July 1, 1987): 724–26. http://dx.doi.org/10.1093/jaoac/70.2.724.

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Abstract The AutoVap® 600 system, used in conjunction with an automated gel permeation chromatography (GPC) instrument, automatically collects and evaporates the effluent from the GPC column, dissolves the residue in a fixed volume of desired solvent, and quantitatively transfers it to a sealed vial. This system was evaluated and found to automate efficiently the cleanup of butterfat for pesticide residue analysis. Quantitative recoveries were obtained for each of 4 pesticides fortified in butterfat and cleaned up through the system and for 12 pesticide standards in the absence of sample matrix collected through the system. After loading, the system operates unattended and will automatically prepare up to 23 individual fat samples for determination by gas chromatography without additional cleanup.
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12

Hopper, Marvin L., and Kenneth R. Griffitt. "Evaluation of an Automated Gel Permeation Cleanup and Evaluation System for Determining Pesticide Residues in Fatty Samples." Journal of AOAC INTERNATIONAL 70, no. 4 (July 1, 1987): 724–26. http://dx.doi.org/10.1093/jaoac/70.4.724.

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Abstract The AutoVap® 600 system, used in conjunction with an automated gel permeation chromatography (GPC) instrument, automatically collects and evaporates the effluent from the GPC column, dissolves the residue in a fixed volume of desired solvent, and quantitatively transfers it to a sealed vial. This system was evaluated and found to automate efficiently the cleanup of butterfat for pesticide residue analysis. Quantitative recoveries were obtained for each of 4 pesticides fortified in butterfat and cleaned up through the system and for 12 pesticide standards in the absence of sample matrix collected through the system. After loading, the system operates unattended and will automatically prepare up to 23 individual fat samples for determination by gas chromatography without additional cleanup.
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13

Lin, L., S. Nakagame, Y. Yao, M. Yoshioka and N. Shiraishi, and N. Shiraishi. "Liquefaction Mechanism of β-O-4 Lignin Model Compound in the Presence of Phenol under Acid Catalysis. Part 2. Reaction Behaviour and Pathways." Holzforschung 55, no. 6 (November 6, 2001): 625–30. http://dx.doi.org/10.1515/hf.2001.102.

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Summary By means of high performance liquid chromatography (HPLC) and gel permeation chromatography (GPC), the yields of the main reaction products and the polymeric portion formed in the reaction of guaiacylglycerol-β-guaiacyl ether (GG) under various acid-catalyzed conditions were quantified as a function of reaction time. Based on their forming sequence and reaction behavior, as well as their structural characteristics, an acid-catalyzed reaction mechanism of GG with phenol was proposed.
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14

Gupta, H. K., and R. Salovey. "Characterization of Ban Copolymers." Rubber Chemistry and Technology 58, no. 2 (May 1, 1985): 295–303. http://dx.doi.org/10.5254/1.3536067.

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Abstract Molar mass and compositional distributions in copolymers of butadiene and acrylonitrile have been analyzed by gel permeation chromatography with multiple detection. In some cases, a third component could not be separated by size-exclusion chromatography and was presumed to be an antioxidant attached to the copolymer chains. The amount of this antioxidant was measured by ultraviolet detection at 280 nm of chromatographic effluents and found to increase in amount with decreasing molar volume. Molar mass and compositional distributions were derived from corrected ultraviolet responses at 254 nm coupled with refractive index detection of BAN solutions separated by GPC. The variation of composition with molecular size depends on the composition of the monomer feed and, presumably, the conversion. For copolymers close the azeotropic composition (36% ACN), the composition was fairly uniform over the entire molecular weight distribution and showed a single Tg by differential scanning calorimetry. Some of the materials showed gel or insoluble fractions which had to be separated from the soluble moieties prior to GPC. Copolymers of composition slightly above azeotropic showed a single Tg but could be separated into sol and gel fractions which differed in composition. Infrared and calorimetric analysis showed that, in these cases, the gel was enriched in acrylonitrile. A sample containing 20% acrylonitrile showed marked deviations from compositional uniformity, and the high molecular weight components were enriched in butadiene. Infrared and calorimetric analysis of the sol and gel fractions showed that they were enriched in acrylonitrile and butadiene, respectively. In fact, the elastomer evidenced two glass transition temperatures. We suggest that gel permeation chromatography with multiple detection, specifically refractive index and ultraviolet absorption at 254 and at 280 nm, permits a fairly complete characterization of BAN elastomers. With computer analysis, a sophisticated raw material quality control is feasible and simple. We plan to reexamine our assumptions using laboratory synthesized BAN copolymers. Moreover, we hope to relate the physical properties of elastomers and rubber compounds with the molecular characterization of BAN copolymers. As an alternative to ultraviolet detection in GPC, it may be possible to get a more complete functional group analysis by infrared spectroscopy.
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15

Li, Shun, Qi Jun Yu, Jiang Xiong Wei, and Zi Yun Wen. "Synthesis and Dispersibility of Polycarboxylate Copolymers with Poly(ethylene oxide) Side Chain." Advanced Materials Research 250-253 (May 2011): 401–4. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.401.

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Polycarboxylate copolymers (PCs) with poly(ethylene oxide) (PEO) side chain were synthesized using first an esterification reaction technique and second a free radical polymerization in aqueous solution. The resultant PCs have been characterized by Fourier transform infrared (FTIR) spectrum and gel permeation chromatography (GPC). The molecular structural parameters of PCs were determined from GPC and ion chromatography (IC). The dispersibility of PCs having different degree of polymerization (DP) of PEO side chain was investigated in cementitious system. Also, the mechanism of dispersion was discussed via the respect of electrostatic repulsion and steric hindrance effect. The results show that the PCs possessing an appropriate DP of PEO side chain can exhibit a higher dispersibility.
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16

Musial, Charles J., and John F. Uthe. "Rapid, Semimicro Method for Determination of Polycyclic Aromatic Hydrocarbons in Shellfish by Automated Gel Permeation/Liquid Chromatography." Journal of AOAC INTERNATIONAL 69, no. 3 (May 1, 1986): 462–66. http://dx.doi.org/10.1093/jaoac/69.3.462.

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Abstract A simple, rapid, easily automated method is described for the determination of polycyclic aromatic hydrocarbons (PAHs) in shellfish such as American lobster (Homarus americanus) and blue mussel (Mytilus edulis). PAHs are extracted from small amounts (1-8 g) of tissue by saponification in IN ethanolic potassium hydroxide followed by partitioning into 2,2,4-trimethylpentane. This solution is evaporated just to dryness by rotary evaporation and the residue is dissolved in cyclohexane- dichloromethane (1 + 1) for gel permeation chromatography (GPC) on Bio-Beads SX-3. The GPC procedure is ideal as a screening method in the range 25-18 000 ng PAHs/g tissue. If individual PAH measurements are required, the appropriate GPC fraction is collected and PAHs are separated by reverse phase liquid chromatography (LC) with fiuorometric detection. Individual PAHs at concentrations as low as 0.25-10 ng/g can be determined. Recoveries of added fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[A]fluoranthene, benzo[b]fluoranthene, benzo[α]pyrene, dibenz[a,h]anthracene, benzo[ghi]perylene, and indeno[l,2,3-cd]pyrene were quantitative, with relative standard deviations ranging from 0.0 to 16.9%.
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17

Shen, Yi, Adam Roberge, Rui Tan, Megan Y. Gee, Dylan C. Gary, Yucheng Huang, Douglas A. Blom, Brian C. Benicewicz, Brandi M. Cossairt, and Andrew B. Greytak. "Gel permeation chromatography as a multifunctional processor for nanocrystal purification and on-column ligand exchange chemistry." Chemical Science 7, no. 9 (2016): 5671–79. http://dx.doi.org/10.1039/c6sc01301e.

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18

Prudnikova, E. V., S. G. Dyachkova, and Zh N. Artemeva. "Gel-permeation chromatography as a method for monitoring transformations of heavy petroleum fractions during secondary oil refining." Industrial laboratory. Diagnostics of materials 87, no. 8 (August 21, 2021): 5–11. http://dx.doi.org/10.26896/1028-6861-2021-87-8-5-11.

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A rapid and easy to use method for monitoring transformations of heavy oil fractions during secondary processes of oil refining is proposed. The method is based on the study of changes in the molecular weight characteristics by gel-permeation chromatography (GPC) using a refractometric detector. Optimal conditions for registration of the chromatograms (temperature, eluent consumption and its composition) were specified. Heptane, toluene, and toluene added with 1% and 5% of methanol were studied as eluents, the polarity indices being arranged in a series 0.2; 2.4; 2.43; 2.54. The effect of the nature of the solvent on the type of the product chromatogram is determined. It is shown that addition of a polar solvent to a nonpolar one increases the polarity index, reduces both the degree of association of petroleum molecules and adsorption on the gel. The most available toluene which meets the GPC requirements is chosen as an eluent. Addition of 1% CH3OH to the eluent promotes suppression of polyelectrolyte effects and adsorption. The revealed absence of the dependence of the retained volume and the type of chromatograms on the eluent flow rate and temperature indicates that separation is carried out under conditions of exclusion and completely obeys the theory of exclusive liquid chromatography. The transformation of raw materials during a technological process of oil production at the JSC «ANKhK» was studied using the GPC method under above-mentioned chromatographic conditions. We have studied vacuum distillate of the primary oil refining unit ELOU+AVT-6 (VD) and the product of hydrocracking of the vacuum distillate of the 123PM unit (HVD). It is shown that determination of the molecular weight characteristics provides an important information about the behavior of technological processes. The HVD meets the requirements for hydrocracking products. A decrease in the content of aromatic hydrocarbons in comparison with the raw feedstock is proved by the data of thin layer chromatography (TLC).
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19

Kang, Zong Hua, and Chang Lu Wang. "Synthesis and Crystallization of Poly(butylenes succinate-block-butylene sebacate)." Advanced Materials Research 750-752 (August 2013): 1313–17. http://dx.doi.org/10.4028/www.scientific.net/amr.750-752.1313.

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A series of aliphatic biodegradable poly (butylene succinate-block-butylene sebacate) (PBSuBSe) copolyesters were synthesized by incorporation of PBSe into the PBSu molecular chains. The molecular weight, crystallization behaviors and the crystal structure of the copolyesters were investigated by using gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD), respectively. The copolyesters might be potentially useful as the biodegradable materials.
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20

Gilbin, Rodolphe, Elena Gomez, and Bernadette Picot. "Phosphorus and organic matter in wetland sediments: analysis through gel permeation chromatography (GPC)." Agronomie 20, no. 5 (July 2000): 567–76. http://dx.doi.org/10.1051/agro:2000151.

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21

Ueno, Eiji, Harumi Oshima, Hiroshi Matsumoto, Isao Saito, and Hiroto Tamura. "Determination of Spinosad in Vegetables and Fruits by High-Performance Liquid Chromatography with UV and Mass Spectrometric Detection After Gel Permeation Chromatography and Solid-Phase Extraction Cleanup on a 2-Layered Column." Journal of AOAC INTERNATIONAL 89, no. 6 (November 1, 2006): 1641–49. http://dx.doi.org/10.1093/jaoac/89.6.1641.

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Abstract A simple and reliable method was developed for the determination of spinosyns A and D, the active ingredients of spinosad, in vegetables and fruits, by high-performance liquid chromatography with UV detection (HPLC-UV) and confirmation by mass spectrometry (MS); the method uses selected gel permeation chromatography (GPC) and a 2-layered column for solid-phase extraction system. An aliquot of the crude sample extract obtained by acetonitrile extraction is loaded into the GPC system. The fraction containing spinosyns A and D is selectively collected and loaded directly onto a 2-layered column consisting of graphitized carbon (upper layer) and cyclohexyl-bonded silica gel (lower layer). After the column is washed with the GPC mobile phase acetonecyclohexane (3 7), the column is eluted with acetonitrile containing 2% triethylamine. The eluate is used for HPLC-UV/MS analysis. Average recoveries from fortified cabbage, green perilla, fig, and strawberry at analyte concentrations of 0.05 and 0.25 μg/g were >85%, and the relative standard deviations were <9%. The detection limits for spinosyns A and D in green perilla were 0.005 g/g by UV detection and 0.001 g/g by MS detection.
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22

Knaul, Jonathan Z., Mohammad R. Kasaai, V. Tam Bui, and Katherine AM Creber. "Article." Canadian Journal of Chemistry 76, no. 11 (November 1, 1998): 1699–706. http://dx.doi.org/10.1139/v98-175.

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Starting from a chitosan sample with a degree of deacetylation of 71%, three separate sample sets were generated by successive deacetylation and reacetylation processes. The degree of deacetylation of samples was determined by UV spectrometry supported by thermogravimetric analysis. The molecular weight of chitosan samples was determined in a solvent system of 0.25 M CH3COOH/0.25 M CH3COONa, using viscometry and gel permeation chromatography (GPC) with a TSK-gel column. The first set of samples had a similar degree of deacetylation (DDA) but differing molecular weights. The second set of samples had a similar molecular weight but differing degrees of deacetylation. The Mark-Houwink-Sakurada constants used for the determination of viscosity average molecular weight and the universal calibration of the GPC system were K = 1.40 × 10-4 dL/g and a = 0.83. Results showed that molecular weights determined from both techniques are in good accord only at lower degrees of deacetylation. This may be attributed to the fact that the chemical structure of chitosan samples could have been largely altered with increasing or decreasing degree of deacetylation. Nevertheless, the trend with which the molecular weights vary with the deacetylation time is consistent over a limited DDA range. A literature review of molecular weight analysis of chitosan is included.Key words: chitosan, degree of deacetylation, gel permeation chromatography, molecular weight, viscometry.
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23

Jiang, You Qing, and Yun Bo Zhang. "Interaction and Molecular Weight Distribution Behavior in Polymer Blends of Styrene-Butadiene-Rubber and Bitumen." Advanced Materials Research 168-170 (December 2010): 973–80. http://dx.doi.org/10.4028/www.scientific.net/amr.168-170.973.

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Styrene-Butadiene-Rubber (SBR) modified bitumen had improved properties in softening points, ductility, and aging resistance. It is due to variation of molecular weight (MW) and molecular weight distribution (MWD) of the product made during the blending between SBR and bitumen. Gel permeation chromatography (GPC) analytical results indicated interaction in polymer blends that bitumen macromolecular chain biting and chemical forces as well as intermolecular recombination formed new bitumen polymer blends.
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24

Wang, Ning, and Xiao Dan Hu. "Synthesis and Photophysical Properties of Side-Chain Polyfluorenes." Applied Mechanics and Materials 865 (June 2017): 60–63. http://dx.doi.org/10.4028/www.scientific.net/amm.865.60.

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In this paper, we reported one vinylfluorene derivative 9,9-dihexyl-vinylfluorene and its corresponding polymers. The monomer and polymers were characterized by NMR, UV-Vis, PL and Gel Permeation Chromatography (GPC). Compared with the monomer, the polymers showed blue-shift in UV-Vis spectra but red-shift in PL spedtra. This kind of side-chain polyfluorenes could be candidates of blue OLED, organic solar cells, and so on.
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25

Jiang, Tao, and Xiang Lu Gao. "Preparation of Polyethylene with Vanadium/Titanium Bi-Metal Ziegler-Natta Catalysts." Applied Mechanics and Materials 665 (October 2014): 335–38. http://dx.doi.org/10.4028/www.scientific.net/amm.665.335.

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The catalyst with magnesium chloride supported vanadium/titanium bimetallic Ziegler-Natta catalysts has been prepared. The effects of V/Ti molar ratio and dosage of α-olefin on catalytic activity of ethylene polymerization were investigated. Gel permeation chromatography (GPC),13C-NMR spectra and differential scanning calorimetry (DSC) analysis were performed to characterize the polymers. The results indicated that the bimetallic catalyst system produced PE with broad and bimodal MWD.
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26

Zhang, Hua, Zhen Yu Wang, Zi Luan Fan, Xin Yang, Xue Wang, and Ning Zhang. "Radiation Protection of Carboxymethylation of an Acid Polysaccharides Extracted from Auricularia Auricula against Uvb In Vitro." Advanced Materials Research 365 (October 2011): 199–204. http://dx.doi.org/10.4028/www.scientific.net/amr.365.199.

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This paper reports on a water-soluble acid polysaccharide (AAP) and in how it was extracted from Auricularia auricular, acquired by CTAB, and prepared it’s carboxymethylation. Chemical characterization by high-performance liquid chromatography/gel permeation chromatograph (HPLC/GPC), Fourier transform infrared (FT-IR) spectrometer and gas chromatography–mass spectrophotometer (GC–MS) were investigated. Chemical analysis indicated that C AAAP was composed of arabinose, xylose, mannose, glucose and galactose, with the molar ratio at 0.04: 0.13: 1.00: 0.59: 0.29. Moreover, radiation protection against UVB in vitro indicated that at the dose range of 200–500 μg/mL, C AAAP enhanced the protection of HepG2 cells against UVB cytotoxicity than AAAP. However, but at the dose range of 50–150 μg/mL the result was just opposite.
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27

Cai, HuiMei, GuangZhi Shang, JuZhou Zhang, GuShuai Tao, GuiJie Chen, and XiaoChun Wan. "Determination of 10 photo-initiator residues in food plastic packaging by gel permeation chromatography extraction coupled with gas chromatography-mass spectrometry." Analytical Methods 7, no. 21 (2015): 9026–31. http://dx.doi.org/10.1039/c5ay01275a.

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28

Lebel, Guy L., and David T. Williams. "Determination of Halogenated Contaminants in Human Adipose Tissue." Journal of AOAC INTERNATIONAL 69, no. 3 (May 1, 1986): 451–58. http://dx.doi.org/10.1093/jaoac/69.3.451.

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Abstract <A method has been developed for determination of organochlorine contaminants in human adipose tissue. After fat extraction from the tissue with acetone-hexane (15 + 85, v/v), organochlorines were fractionated from fat by gel permeation chromatography with methylene chloride-cyclohexane (1 + 1, v/v) as solvent. After Florisil column cleanup, the GPC extract was analyzed by capillary column gas chromatography using 2 columns of different polarity. Compound identity was confirmed by gas chromatography-mass spectrometry using selected ion monitoring. Recoveries for fortification levels of 10-500 ng/g were greater than 80 % except for trichlorobenzene and hexachlorobutadiene (ca 60%).
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29

Higashi, K., and K. Hagiwara. "Identification of Oil Spilled at Sea by High Performance Gel Permeation Chromatography Pattern Recognition." Water Science and Technology 20, no. 6-7 (June 1, 1988): 55–62. http://dx.doi.org/10.2166/wst.1988.0189.

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Oil pollution in the marine environment has now become a world-wide concern. Recently, in Japan, over 1,000 cases of oil pollution have been occurring every year. It is important to develop an effective identification method for spilled oils for conservation of marine environments. A new method was developed using high performance gel permeation chromatography (GPC). Chromatograms of the molecular weight distribution of oils were obtained using an ultra-violet (UV) detector. Pattern similarities between pairs of chromatograms were calculated by section areas of the chromatograms using a computer. Sixty two kinds of crude oil imported by Japan were classified by this method, and a close relationship was found between the countries of origin of the crude oils and their chromatographic patterns. Forty nine tar balls sampled from Japanese coasts were compared with the crude oils, and the origins of the tar balls were deduced. The proposed method was effective for the identification of spilled oils, and had high sensitivity and reproducibility.
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30

Zhou, Si Kai, Ya Juan Xu, Shao Ming Fang, and Zhi Jun Chen. "The Synthesis of Polystyrene-B-Poly(4-Vinylpyridine) by Nitroxide-Medium Controllable Free Radical Polymerization." Advanced Materials Research 531 (June 2012): 366–69. http://dx.doi.org/10.4028/www.scientific.net/amr.531.366.

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In this paper, a system polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) were synthesized by nitroxide-medium controllable free radical polymerization. PS-b-P4VP were characterized by 1H-nuclear magnetic resonance (1H-NMR), infrared spectrum (FTIR) and gel permeation chromatography (GPC). The results have indicated that diblock copolymers can be prepared and with molecular polydispersities in the range of 1.08 to 1.31. The structure of diblock was showed by 1H-nuclear magnetic resonance.
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31

Czuczwa, Jean M., and Ann Alford Stevens. "Optimized Gel Permeation Chromatographic Cleanup for Soil, Sediment, Wastes, and Oily Waste Extracts for Determination of Semivolatile Organic Pollutants and PCBs." Journal of AOAC INTERNATIONAL 72, no. 5 (September 1, 1989): 752–59. http://dx.doi.org/10.1093/jaoac/72.5.752.

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Abstract A gel permeation chromatographic (GPC) method, used by the U.S. Environmental Protection Agency (USEPA), was modified for cleanup of soil, sediments, wastes, and oily wastes before determination of semivolatile organic pollutants. The modifications included new calibration procedures and control of the amount of material processed. The modifications were evaluated for soil and sediment matrixes in a 5-laboratory study where each laboratory processed a solution containing a phthalate, substituted phenols and benzenes, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), nitroaniline, and pesticides. With the exception of nitroaniline, analyte recoveries were 87-112%, with relative standard deviations (RSDs) of 6.7-26%. Soil samples containing PCBs and fortified with 6 pesticides at 0.7-4 /ig/g were also analyzed by the 5 laboratories. The mean recovery of the 6 pesticides was 100% with a mean RSD of 16%. Mean RSD for the determination of total PCBs was 8.9%. An additional modification for the processing of wastes and high concentration waste samples was attempted; this involved GPC processing of sample extracts dissolved in 1 + 1 butyl chloridemethylene chloride. This modification did not improve recoveries of the semivolatile analytes. Finally, the modified GPC protocol was applied to PCB-contaminated reclaimed waste oils samples. Two GPC cleanup steps were used to separate PCBs from the waste oil samples before PCBs were determined by gas chromatography combined with electron-capture detection (GC/ECD).
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32

Zhan, Xue-Hui. "Fe-mediated ICAR ATRP of methyl methacrylate on photoinduced miniemulsion polymerization." e-Polymers 16, no. 1 (January 1, 2016): 41–47. http://dx.doi.org/10.1515/epoly-2015-0072.

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AbstractThe initiators for continuous activator regeneration (ICAR) atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) were investigated in microemulsion under light irradiation with ethyl 2-bromoisbutyrate (EBiB) as an ATRP initiator, ferric chloride hexahydrate (FeCl3·6H2O) as a catalyst, N,N,N′,N′-tetramethyl-1,2-ethanediamine (TMEDA) as a ligand, and azobisisobutyronitrile (AIBN) as an initiator and reducing agent. The linear dependence of ln([M]0/[M]) on polymerization time was observed, indicating that the polymerization was living polymerization. Furthermore, the number-average molecular weights (Mn), gel permeation chromatography (GPC) and molecular weight distributions (MWD) of the PMMA obtained from GPC were controlled. The product was characterized by 1H nuclear magnetic resonance (NMR) and GPC. The living features were verified by chain-extended with MMA with the obtained PMMA as macroinitiator.
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33

Beljaars, Paul R., Remmelt Van Dijk, and Adrie A. M. Houwen-Claassen. "Determination of Polymerized Triglycerides in Frying Fats and Oils by Gel Permeation Chromatography: Interlaboratory Study." Journal of AOAC INTERNATIONAL 77, no. 3 (May 1, 1994): 667–71. http://dx.doi.org/10.1093/jaoac/77.3.667.

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Abstract An interlaboratory study of the gel permeation chro-matographic (GPC) determination of polymerized triglycerides (PTG) in frying fats and oils was conducted by the Project Group on Collaborative Studies (PCS) of the Inspectorate for Health Protection, Food Inspection Service, The Netherlands. Thirteen laboratories participated in this study, which was focused on thermally abused oil and fat samples containing dimerized and polymerized triglycerides at levels just below and far above the Dutch regulatory limit of 16% (m/m). Samples were dissolved in tetrahydrofuran (THF) and analyzed on a GPC system, using THF as the mobile phase. Refractive index (Rl) detection was used to determine PTG. Six heat-processed fat samples containing from 14 to 28% (m/m) PTG at 3 different levels (3 pairs of split level samples) were single analyzed according to the proposed procedure. Data analysis was performed according to the International Union of Pure and Applied Chemistry/International Organization for Standardization/AOAC protocols for statistics. The results of 2 collaborators were identified as outliers at the 20% (m/m) PTG level by applying the paired Grubbs test at the 1% level of significance. The repeatability relative standard deviation (RSDr) values ranged from 0.48 to 2.25%, whereas the reproducibility relative standard deviation (RSDr) values ranged from 1.34 to 4.57%.
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34

Su, Na, and Zheng Min Cao. "Preparation and Characterization of Poly(Dimethyl Diallyl Ammonium Chloride)/Modified SiO2 Spherical Brushes." Applied Mechanics and Materials 731 (January 2015): 569–72. http://dx.doi.org/10.4028/www.scientific.net/amm.731.569.

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Novel cationic spherical polyelectrolyte brushes (CSPB) consisting of γ-methacryloxypropyl trimethoxy-silane (KH-570) modified SiO2cores and poly (Dimethyl diallyl ammonium chloride) (PDMDAAC) brushes were prepared by conventional free radical polymerization. The resulting CSPB were characterized by Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), and Thermo-gravimetric analysis (TGA). After cleaving the polyelectrolyte chains from the anchoring surface, the molecular weight of brushes was 1.824×103gmol-1from Gel Permeation Chromatography (GPC) measurements.
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35

Wang, Chun, Qing Li, Jian Hua Yang, Jun Ya Wada, Takahiko Kawai, Yoshinori Kasai, Hisato Hayashi, and Shinichi Kuroda. "Synthesis and Characterization of Poly(Methyl Methacrylate) -Grafted-Cellulose Nanofiber." Applied Mechanics and Materials 423-426 (September 2013): 159–62. http://dx.doi.org/10.4028/www.scientific.net/amm.423-426.159.

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Poly (methyl methacrylate) (PMMA)-graft-cellulose nanofibers (CeNFs) (PMMA-g-CeNF) were synthesized by means of graft-polymerization using Azo initiator in aqueous medium. The synthesized grafted fibers were characterized by Fourier transform infrared spectroscopy (FT-IR). Then, PMMA-g-CeNF were hydrolyzed by acid hydrolysis method with different acid constant and hydrolysis time and characterized by gel permeation chromatography (GPC). Finally, PMMA-g-CeNF was characterized by thermo-gravimetric and differential thermal analyses (TG-DTA).
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36

MATSUBARA, Hidetaka, Yayoi IMAMURA, and Futosi KOYAMA. "Fractionation of offensive odorous substances in a Pig’s feces by gel permeation chromatography (GPC)." Journal of Japan Association on Odor Environment 45, no. 2 (2014): 143–52. http://dx.doi.org/10.2171/jao.45.143.

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37

Zhao, Li Hong, and Hong Jun Sun. "Comparative Study of Two Types of Alkali Lignin from Different Origin." Advanced Materials Research 299-300 (July 2011): 747–50. http://dx.doi.org/10.4028/www.scientific.net/amr.299-300.747.

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The physico-chemical characterization of two types of alkali lignin from different origin, namely L1 and L2, were studied by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectrometry (1H NMR) and gel permeation chromatography (GPC) analysis. FT-IR spectra show that they have the characteristics of absorption peaks of syringyl and guaiacyl. 1H NMR spectra indicate that acetylated L1 exhibits higher content of aromatic protons than L2, as the former is mainly composed by G units. L2 presents high quantities of methoxyl groups. GPC results show that L1 has much higher weight average than L2. They had similar functional groups, however, there were differences in the relative contents of functional groups.
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38

Chen, Si, Jian Ming Xu, Guo Dong Tang, and Xu Wang. "Gelator In Situ Modify PMMA." Applied Mechanics and Materials 130-134 (October 2011): 1528–31. http://dx.doi.org/10.4028/www.scientific.net/amm.130-134.1528.

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Gelator (G2-C12-G2) was synthesized successfully, the structure of which was confirmed by1H-NMR and Mass spectra (MS). And G2-C12-G2was used to modify PMMA by “in-situ” polymerization. The results of gel permeation chromatography (GPC) showed that Mn and Mw/Mnof the PMMA composite were barely influenced by the incorporation of gel. The results of dynamic mechanical analysis (DMA) showed that the modified PMMA had higher modulus, toughness and glass transition temperature (Tg) than pure PMMA. Furthermore the results of spectrophotometer showed that the transparency of modified PMMA was nearly the same as pure PMMA .
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39

Blanco, María, Noelia Sanz, Jesús Valcarcel, Ricardo I. Pérez-Martín, and Carmen G. Sotelo. "Does Subunit Composition Influence the Intermolecular Crosslinking of Fish Collagen? A Study with Hake and Blue Shark Skin Collagens." Polymers 12, no. 8 (August 3, 2020): 1734. http://dx.doi.org/10.3390/polym12081734.

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Acid-soluble collagens from European hake and Blue shark skin were isolated, characterized, and compared. As the structure of collagen determines its function, the final objective of this study was to investigate biochemical differences between both collagens to identify future potential applications. Chromatographic behavior revealed differences in collagen from both species. Increases of temperature and stirring time produced no effect on European hake collagen solubility in the mobile phase, resulting in the same chromatographic profiles. Conversely, the application of temperature and stirring-time increments showed a positive effect on Blue shark collagen solubility, resulting in different chromatographic profiles and observing higher molecular weight components when sample is incubated at 50 °C (15 min) after 48 h stirring. To test if the different chromatographic behavior exhibited by both collagens could be influenced by differences in subunit composition (alpha-chains), cation exchange chromatography was employed to separate collagen subunits. The electrophoretic patterns and gel permeation chromatography with light-scattering detection (GPC-LS) results of the obtained cation exchange peak fractions revealed differences regarding subunit composition between both species, influencing the crosslinking pattern. This is the first comparative study using GPC-LS to provide information of European hake and Blue shark collagen subunit composition.
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40

Pang, Guo-Fang, Yan-Zhong Cao, Chun-Lin Fan, Guang-Qun Jia, Jin-Jie Zhang, Xue-Min Li, Yong-Ming Liu, et al. "Analysis Method Study on 839 Pesticide and Chemical Contaminant Multiresidues in Animal Muscles by Gel Permeation Chromatography Cleanup, GC/MS, and LC/MS/MS." Journal of AOAC INTERNATIONAL 92, no. 3 (May 1, 2009): S1—S72. http://dx.doi.org/10.1093/jaoac/92.3.s1.

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Abstract The paper reports the study of gel permeation chromatography (GPC), gas chromatography/mass spectrometry (GS/MS), and column chromatography tandem MS (LC/MS/MS) for 839 pesticides and chemical contaminants, through which a GPC data bank has been established for 744 pesticides, a GC/MS data bank for 541 pesticides, and an LC/MS/MS data bank for 464 pesticides. On the basis of this study, a new method for quantitative determination of 587 pesticide residues in animal muscles such as beef, mutton, pork, chicken, and rabbit has been established using GPC cleanup followed by GC/MS and LC/MS/MS. In the method, 10 g animal samples were mixed with 20 g sodium sulfate and extracted twice with 35 mL cyclohexaneethyl acetate (1 + 1) by blender homogenization followed by centrifugation, filtration, and concentration. An equivalent of 5 g sample was injected into a 400 25 mm S-X3 GPC column, with cyclohexaneethyl acetate (1 + 1) as the mobile phase at a flow rate of 5 mL/min. The 2240 min fraction was collected for subsequent analysis. For the 478 pesticides determined by GC/MS, the portions collected from GPC were concentrated to 0.5 mL and exchanged twice with 5 mL hexane. For the 379 pesticides determined by LC/MS/MS, the portions collected from GPC were dissolved with acetonitrilewater (60 + 40) after taking the extract to dryness with nitrogen gas. At the limit of quantification (LOQ) and 10 LOQ fortification levels of 0.116 000 g/kg, recoveries were within 40130, among which 563 pesticide recoveries were between 60 and 130, accounting for 96 of the compounds; 24 analytes were recovered between 40 and 60, accounting for 4 of the compounds. The relative standard deviation was below 30 for all 587 pesticides. The limits of detection for the method were 0.11600 g/kg. In comparison with GC/MS, LC/MS/MS increased the detection sensitivity 21000 times for 236 pesticides.
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41

Wang, Jing Chang, Chun Ming Liu, Qi Cheng Zhao, and Xu Dong. "Synthesis of Poly(acrylic Acid Dodecyl Ester-Styrene-Maleic Anhydride) Terpolymer and Surface Modification of Glass Fiber." Advanced Materials Research 690-693 (May 2013): 1645–48. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.1645.

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Poly(acrylic acid dodecyl ester-styrene-maleic anhydride) terpolymer (LA-St-MA) is synthesized by free-radical solution polymerization and is used for surface modification of glass fiber. Terpolymer is characterized by Fourier transform-infrared spectroscopy (FT-IR) and gel permeation chromatography (GPC). Meanwhile, scanning electron microscopy (SEM) is adopted to observe surface properties of modified glass fiber. The results reveal synthetic terpolymer can be coated on glass fiber surface well and that modified glass fiber can be bonded well with polypropylene(PP).
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42

Cheng, Zheng Zai, Yu Jing Nie, Xiao Chao Yan, Rui Lei, and Su Su Lin. "Polymerization of Methyl Methacrylate with a Novel Titanium Complex." Advanced Materials Research 179-180 (January 2011): 1203–7. http://dx.doi.org/10.4028/www.scientific.net/amr.179-180.1203.

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Novel titanium complex [2-O-(5- NO2)C6H3CH=N[(C6H4) –2-O ]]2TiCl2 (1) has been prepared by treatment of the ligand complex 1a with TiCl4•2THF in dichloromethane solution. The complex 1a and 1 were characterized by 1H-NMR . Activated by MAO, Complex 1 displayed very high activity for methyl methacrylate polymerization and the viscosity-average molecular weight of PMMA is more than 35×104 at 60°C.The molecular-weight distribution of PMMA measured by gel permeation chromatography (GPC) is narrow.
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43

Hiran, B. L., S. N. Paliwal, Jyoti Choudhary, and P. R. Choudhary. "Synthesis, Characterization and Copolymerization of N-(phenylamino)maleimide with MMA." E-Journal of Chemistry 4, no. 2 (2007): 265–71. http://dx.doi.org/10.1155/2007/234768.

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The free radical copolymerization of N-(phenylamino)maleimide (N-PAMI) was carried. The copolymerization with methyl methacrylate (MMA) was performed at 65°C with AIBN as the initiator in THF solvent. Resulting copolymer was characterized by density measurement, intrinsic viscosity, solubility, FT-IR &1H NMR spectroscopy. Effect of the solvent and time on copolymer yield was also investigated. The molecular weight of copolymer was determined by gel permeation chromatography (GPC). The thermal stability of copolymer was determined by Thermogravimetric analysis (TGA).
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44

Hakemi, H. "Evidence of Chemical Reaction in Binary Blends of Polycarbonate and a Semi-Flexible Liquid Crystal Polymer." Journal of Research Updates in Polymer Science 10 (July 19, 2021): 58–68. http://dx.doi.org/10.6000/1929-5995.2021.10.8.

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In this study, we provide the experimental results of the binary blends of a semi-flexible nematic liquid crystal polymer (LCP1) and polycarbonate (PC) within their phase diagram. The LCP1/PC blends were investigated by Differential Scanning Calorimetry (DSC), Optical Microscopy (OM), Wide-angle X-Ray Diffraction (WXRD), Fourier Transfer Infrared (FTIR), Gel Permeation Chromatography (GPC), and Nuclear Magnetic Resonance (NMR) techniques and observed the evidence of chemical reaction between LCP1 and PC in their heat-treated blends possibly by transesterification mechanism.
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45

Qian, Yong, Yonghong Deng, Yunqing Guo, Conghua Yi, and Xueqing Qiu. "Determination of absolute molecular weight of sodium lignosulfonates (NaLS) by laser light scattering (LLS)." Holzforschung 67, no. 3 (April 1, 2013): 265–71. http://dx.doi.org/10.1515/hf-2012-0063.

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Abstract The problems related to the determination of the absolute molecular weight (Mw) of sodium lignosulfonate (NaLS) are the focus of the present work. Four narrow-dispersed NaLS fractions were collected by filtration, ultrafiltration, and gel permeation chromatography (GPC), and their Mw measured by laser light scattering (LLSMw) was compared with that obtained by GPC (GPCMw). The LLSMw values were much larger than GPCMw, and this Mw difference increased with increasing Mw of NaLS. This finding confirms the known polyelectrolyte and aggregation effects of NaLS. The deviation is also partly due to the conformation differences between the GPC standard (sodium polystyrene sulfonate) and the NaLS molecules. The effects of polyelectrolytes and NaLS aggregates could be inhibited by adding enough NaCl salt in the NaLS solution and filtering the NaLS/NaCl solution through a syringe filter. As a result, the slow mode in dynamic LLS measurement disappeared. By this approach, the absolute LLSMw values were only slightly larger than that determined by GPC due to the conformation differences between the GPC standard and the NaLS molecules.
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46

Zhang, Xiao Lei, Lei Wang, Xiao Qi Chen, Hai Jun Zhou, Shu Lan Yang, Yan Tao Li, and Wan Bao Qin. "Research on Determination for Food-Related Polystyrene Doped with Recycled Plastic by GPC." Advanced Materials Research 1033-1034 (October 2014): 954–57. http://dx.doi.org/10.4028/www.scientific.net/amr.1033-1034.954.

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Polystyrene (PS) had wide range of applications in food packaging field. Mechanical recycling of PS was simulated by multiple extrusions to assess the behavior of physical degradation. The molecular weight and the molecular weight distribution of PS with different extrusion cycles were investigated by gel permeation chromatography (GPC). Experimental results show that the differential and cumulative distribution curves of PS shift to smaller values with the number of extrusions cycled increasing. The Mn and Mw of PS decrease. However, Polydispersity index (PDI) increases obviously.
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47

Li, Heng, Yuhang Liu, Ning Sun, Zhaohua Xu, Yibiao Li, and Shaohua Jiang. "Unique viscosity mutation of multi-generation hyperbranched waterborne polyurethane." Journal of Polymer Engineering 34, no. 7 (September 1, 2014): 605–9. http://dx.doi.org/10.1515/polyeng-2013-0312.

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Abstract Different generation hyperbranched polyurethanes (HBPUs) were synthesized through the A2+B’B2 strategy. The molecular structures and viscosity were characterized by nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC). The NMR results confirmed the formation of the branched units between the segments contained in the HBPU structure. The GPC with a four-capillary bridge design differential viscometer and the Ubbelohde viscometer showed a different viscosity. For the HBPUs, the viscosity first increased to higher values then decreased to lower values, and finally increased with increasing weight, which can be attributed to the spherical structure. The growth degree of HBPUs spherical structure depends on the forming hydrogen bonds; when the hydrogen bonds reach a certain degree, the spherical structure becomes compact.
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48

OZAWA, HIROAKI, and TAKUJI OGAWA. "SYNTHESIS OF THICK PORPHYRIN MOLECULAR WIRES BY A PALLADIUM CATALYZED OLIGOMERIZATION." International Journal of Nanoscience 01, no. 05n06 (October 2002): 483–87. http://dx.doi.org/10.1142/s0219581x02000541.

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In the aim to prepare thick porphyrin molecular wires, which is visible by atomic force microscopy (AFM), even on the rough surfaces of nanogap electrodes fabricated by electron beam lithography, dendrimer protected porphyrins whose two meso-positions are substituted with ethynyl groups. The porphyrin monomer was reacted with palladium catalyst to make oligomers. Analyses of them with time-of-flight mass spectroscopy (TOF-MS), gel-permeation-chromatography (GPC) revealed that the oligomers were distributed up to 16 mer, whose molecular weight was about 38 000 Daltons.
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49

Kennedy, J. C., J. R. MacCallum, and D. H. MacKerron. "Synthesis and characterization of a series of poly(α,ω-alkyldiynes) and copoly(α,ω-alkyldiynes)." Canadian Journal of Chemistry 73, no. 11 (November 1, 1995): 1914–23. http://dx.doi.org/10.1139/v95-236.

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A series of poly(α,ω-alkyldiynes) and copoly(α,ω-alkyldiynes) were synthesized by catalytic Glaser coupling reactions. Two routes were investigated and developed. These routes were chosen in anticipation that high molar mass, linear and polydisperse, polymers would be achieved. GPC (gel permeation chromatography) curves revealed that this was possible for the majority of polymers synthesized by the first route. However, a wide range of molar masses were obtained by the second route with a significant low molar mass tail present in almost all GPC curves. Very low Mn (number average molar mass) values by GPC gave correspondingly very high Mn values by end-group analysis (EGA). Hence, it was proposed that the low molar mass tail was a consequence of cyclic structures. From these results and observations a mechanism for the polymerization of the α,ω-alkyldiynes was proposed. Keywords: poly(α,ω-alkyldiynes), Glaser coupling, molar mass.
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50

Martinez-López, Sandra, Asuncion Morales-Noé, Agustin Pastor-Garcia, Angel Morales-Rubio, and Miguel de la Guardia. "Sample Preparation Improvement in Polycyclic Aromatic Hydrocarbons Determination in Olive Oils by Gel Permeation Chromatography and Liquid Chromatography with Fluorescence Detection." Journal of AOAC INTERNATIONAL 88, no. 4 (July 1, 2005): 1247–54. http://dx.doi.org/10.1093/jaoac/88.4.1247.

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Abstract The determination of 15 polycyclic aromatic hydrocarbons (PAHs) in olive oil samples has been improved in order to obtain a fast methodology with a low limit of detection through the combination of liquid–liquid extraction with acetonitrile and preparative gel permeation chromatography (GPC) prior to the injection of purified extracts into a C18 column. Acetonitrile–water was used as the mobile phase with a gradient from 50 to 95%, w/w, acetonitrile in 30 min. The oven temperature was maintained at 15°C, and fluorometric detection was made at a fixed excitation wavelength of 264 nm and variable, optimal emission wavelength for each analyte ranging from 352 nm for 11-H-benzo(b)fluorene to 500 nm for indeno(1,2,3-cd)pyrene. Recovery for all the compounds studied varied from 75 to 111%, and limit of detection values from 0.05 ng/g for benzo(k)fluoranthene to 0.48 ng/g for indeno(1,2,3-cd)pyrene, corresponding to 0.09 ng/g benzo(a)pyrene. Results were compared with those obtained by liquid–liquid extraction followed by a cleanup on silica and a direct GPC treatment of oil samples diluted in dichloromethane, 2 other methodologies that are appropriate for quantifying PAHs in olive oils. However, the proposed method improves the determination limits, reduces the time of analysis, and provides a highly stable baseline for sample chromatograms.
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