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CURING KINETICS AND thermal stability.OF EPOXY BLENDS CONTAINING PHOSPHOROUS-OXIRANE WITH AROMATIC AMIDE-AMINE AS CURING AGENTS

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Chinese Journal of Polymer Science 2012年第5期30卷 694-704页

作者： Geeta Durga A.K.Narula School of Basic and Applied Sciences Guru Gobind Singh Indraprastha University

This article describes the synthesis of a series of aromatic amide-amines and their potential use as epoxy hardeners. These amines were synthesized by the reaction of L-phenylalanine （PA） with diamines of different structures i.e. 1,4- phenylene diamine （PD）, 1,5-diamino naphthalene （N）, 4,4＇-（9-fluorenyllidene）-dianiline （F）, 4,4＇-diaminodiphenyl sulphide （DS） and 3,4＇-oxydianiline （O） in a stoichiometric ratio （I ：1）. Structural characterization of synthesized amide-amines was done with the help of elemental analysis and spectroscopic techniques viz. FT-IR, 1H-NMR and 13C-NMR. An epoxy blend was prepared by mixing tris（glycidyloxy） phosphine oxide （TGPO） with conventional epoxy i.e. diglycidyl ether of bisphenol-A （DGEBA） in an equivalent ratio of 2：3 to incorporate phosphorous into the main chain. The curing kinetics of the epoxy blend with synthesized aromatic amide-amines was investigated by non-isothermal DSC technique using multiple heating rate method （5, 10, 15 and 20 K/min.）. The activation energies were determined by fitting the experimental data into Kissinger and Ozawa kinetic models. The activation energies obtained through Ozawa method were slightly higher than those of Kissinger method but were comparable. However, both the energies were found to be dependent on the structure of amines. The thermal stability.and weight loss behavior of isothermally cured thermosets were also investigated using thermogravimetric analysis （TGA） in nitrogen atmosphere. All the samples showed improved thermal stability.in terms of char yield than using only amines as hardeners.

关键词： Phosphorylated epoxy Amide-Amines Curing kinetics Char yield thermal stability.

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Synthesis, Characterization and thermal stability.of Novel Carborane- Containing Epoxy Novolacs

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Chinese Journal of Polymer Science 2016年第9期34卷 1103-1116页

作者： guo han zhen yang xiao-xue yang 张孝阿 sheng-ling jiang ya-fei lu Key Laboratory of Carbon Fiber and Functional Polymers of Ministry of Education College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Carborane bisphenol novolacs （3 and 4） were synthesized in the presence of acid catalyst from carborane bisphenols （5 and 6） and formaldehyde. Further epoxidization of carborane bisphenol novolacs with epichlorohydrin gave carborane bisphenol epoxy novolacs （1 and 2）. The molecular weight and epoxy value of obtained resins were determined using the molecular weight of their precursors. The epoxy values of 1 and 2 were 0.48 and 0.52 respectively, higher than the maximum theoretical epoxy value （0.45） of difunctional carborane bisphenol epoxy resins. FTIR and NMR were utilized to characterize 1 and 2. The curing behaviors were also studied by DSC and the optimized curing conditions were obtained. TGA analysis indicated that carborane moiety could shield its adjacent organic structures against initial decomposition. On the other hand, B--H on carborane cage could react with oxygen to form a three-dimensional network linked by B--O--B and B--C bonds, which further blocked the movement of formed radicals and thus the degradation process was inhibited.

关键词： Carborane Epoxy novolacs thermal stability.

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Influence of Catalyst Residues on Thermo-oxidative Aging and thermal stability.of Poly(butene-1)

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Chinese Journal of Polymer Science 2014年第5期32卷 633-639页

作者： Bao-yu Sun Lei Cui Xiu-bo Jiang Bai-yu Jiang 姚薇贺爱华 Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-Plastics School of Polymer Science and Engineering Qingdao University of Science and Technology

Isotactic poly（butene-1）（iPB） with spherical morphology was synthesized successfully with bulk precipitation polymerization without post-treatment of the products. The bulk precipitation polymerization process made it possible for iPB to be used as general plastic due to the acceptable decreased cost compared with the solution polymerization process. The influence of catalyst residues on the aging and thermal stability.of iPB synthesized by bulk precipitation polymerization method was investigated by gel permeation chromatography, mechanical performance testing, thermogravimetric analysis and infrared spectroscopic analysis. Commercial iPB and the lab-made iPB with varied catalyst residue contents were studied. The results demonstrated that the catalyst residues played an important role in the aging process of the iPB. A possible mechanism of aging promotion by catalyst residues was proposed.

关键词： Catalyst residues Poly(butene-1) Aging thermal stability.

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STUDY ON THE SURFACE MODIFICATION OF NANO-TiO_2 BY GRAFTING PMMA/PBMA AND ITS thermal stability

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Chinese Journal of Polymer Science 2005年第3期23卷 243-247页

作者：宇海银 Jia-shanGu JunDu Ming-yunGuan CollegeofChemistryandMaterialsScience AnhuiNormalUniversityWuhu241000China

The surface of nano-TiO_2 was encapsulated with hydroxyl-propyl-methyl cellulose(HPMC),and then cograftedwith *** of absorbing and grafting have been *** nano-TiO_2 particles were characterized byFT-IR spectra,TEM and TG *** was convinced from FT-IR studies that both methyl methacrylate(MMA)and butyl-methacrylate(BMA)were co-grafted onto the surface of nano-TiO_2 *** images show that the surface of nano-TiO_2 particles was successfully modified by a thick layer of film-like *** results demonstrate that the decompositiontemperature of HPMC-g-PMMA/PBMA,which has been grafted onto the surface of nano-TiO_2,is 56.9 K higher than that ofHPMC-g-PMMA/PBMA.

关键词： Hydroxyl-propyl-methyl cellulose Nano-TiO_2 particles Surface modification Cograft polymerization thermal stability.

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PREPARATION AND CHARACTERIZATION OF INCLUSION COMPLEXES OF TWO-ARM LINEAR AND FOUR-ARM STAR-SHAPED POLY(ε-CAPROLACTONE)S WITHα-CYCLODEXTRIN

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Chinese Journal of Polymer Science 2006年第3期24卷 245-252页

作者： Lu Wang Jing-liang Wang 董常明 Department of Polymer Science ＆ Engineering School of Chemistry and Chemical Technology Shanghai Jiao Tong University Shanghai 200240 China

Both four-ann star-shaped poly（ε-caprolactone）（4sPCL） and two-ann linear PCL （2LPCL） were synthesized and their inclusion complexation with α-cyclodextrin （α-CD） were studied. The inclusion complexes （ICs） formed between the PCL polymers and α-CD were characterized by ^1H-NMR, DSC, TGA, WAXD, and FT-1R, respectively. Both branch ann number and molecular weight of the PCL polymers have apparent effect on the stoichiometry （CL：CD, mol：mol） of these ICs. All these analytical results indicate that the branch arms of the PCL polymers are incorporated into the hydrophobic α-CD cavities and their original crystalline properties are completely suppressed. Moreover, the inclusion complexation between two-ann linear or four-ann star-shaped PCL polymers and α-CD not only enhances the thermal stability.of the guest PCL polymers but also improves that of α-CD.

关键词： Inclusion complexes Linear poly(ε-caprolactone) Star-shaped poly(ε-caprolactone) thermal stability.

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CROSS-LINKING OF AROMATIC POLY(THIOETHER)S

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Chinese Journal of Polymer Science 2007年第5期25卷 509-517页

作者： Matthew M. Yonkey Dillip K. Mohanty Christopher Crouse Zhong-biao Zhang Department of Chemistry Central Mich-igan University Mt. Pleasant M1-48858 USA Department of Chemistry Rice-University Houston TX-77251 USA Department of Chemistry Virginia Tech Blacksburg VA-24060 USA

A novel cross-linking process using two high molecular weight aromatic poly（thioether）s, which were synthesized by the reactions of 4,4＇-thiobisbenzenethiol with 4,4＇-difluorobenzophenone and 4,4＇-difluorodiphenylsulfone, respectively, and commercially available lower molecular weight poly（p-phenylene sulfide） was investigated. These reactions were carried out in bulk by the addition of silver tetrafluroborate and α,α＇-dibromo-p-xylene at 190℃ over a period of 45 min. Furthermore, the same procedure could be modified to cross-link compression-molded films of these three polymers. The thermal and solubility behaviors of these polymers before and after cross-linking reactions, are presented.

关键词： Aromatic poly(thioether)s Chemical cross-linking Solubility thermal stability.

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EFFECT OF NANOCRYSTALLINE CELLULOSE ON THE CURING CHARACTERISTICS AND AGING RESISTANCE PROPERTIES OF CARBON BLACK REINFORCED NATURAL RUBBER

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Chinese Journal of Polymer Science 2013年第10期31卷 1382-1393页

作者： Ju Gu Wan-juan Chen Lu Lin Yuan-fang Luo De-min Jia College of Materials Science and Engineering South China University of Technology

This work focused on the effect of nanocrystalline cellulose （NCC） on the curing characteristics, aging resistance and thermal stability.of natural rubber （NR） reinforced with carbon black （CB）. Sharing the same fillers loading of 45 parts per hundred rubber （phr）, NR/NCC/CB composites with different NCC/CB ratios （i.e. 0/45, 5/40, 10/35, 15/30, 20/25 phr） were prepared and analyzed. Resorcinol and hexamethylene tetramine （RH）, acting as the modifier in NR/NCC interface, was also discussed for its influence. The result showed that an relatively higher ratio of NCC/CB led to a lower torque, a shorter cure time （Tg0）, a slightly longer scorch time （Ti0） and a bigger vulcanization rate constant （K）. This tendency suggested that the existence of NCC accelerated the vulcanization process. Additionally, modified by RH, NR/NCC/CB compounds exhibited a short T10 and a elevated torque. And a moderate RH content would lower the E of vulcanization. A 10 phr substitute of CB by NCC can help to improve aging resistance in terms of mechanical properties. In a high temperature aging condition, composites with 10 phr NCC also performed the highest storage modulus （G＇） among composites tested. A moderate NCC content contributed to the best retention of G＇ after high temperature aging, so did the incorporation of RH. With the partial replacement of CB by NCC, the temperature of 5% weight-lose had a slight drop and the apparent crosslink density showed a decrease. Thanks to the interaction of RH with both NR and NCC, composites showed an improvement in apparent crosslink density after modified by RH.

关键词： Nanocrystalline cellulose Natural rubber Curing characteristics Aging resistance thermal stability.

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CROSSLINKED ORGANOSILOXANE HYBRID MATERIALS PREPARED BY CONDENSATION OF SILANOL AND MODIFIED SILICA: SYNTHESIS AND CHARACTERIZATION

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Chinese Journal of Polymer Science 2013年第7期31卷 974-983页

作者： Da-hai Gao 贾梦秋 Ying Luo College of Materials Science and Engineering Beijing University of Chemical Technology Nuclear Power Institute of China

Hybrid materials based on polymethylphenylsiloxane （PMPS） and organic functionalized silica were synthesized via condensation reaction between silanol and alkoxysilyl groups in the presence of quaternary ammonium hydroxide. The structure of prepared materials was investigated by FTIR and NMR, which indicate that the products have incorporated modified silica into the polymer matrix. The prepared hybrid materials show a satisfactory thermal resistance because the initial decomposition of typical product occurred at nearly 100 K higher than that of the pure polymer according to the thermogravimetric analysis （TGA） results. Differential thermogravimetric analysis （DTGA） data confirm that the thermal degradation of prepared hybrid materials comprises of two steps, of which the first one could be controlled by adjusting the content of silica particles and the ratio of surface groups on the particles. The coating films obtained from hybrid products exhibit good thermal mechanical properties. Therefore, the materials are hoped to be used for the application in thermal resistant coating.

关键词： Hybrid material Crosslinked polysiloxane Condensation polymerization thermal stability.

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SYNTHESIS AND PROPERTIES OF SOLUBLE AROMATIC COPOLYAMIDES CONTAINING PHOSPHINE OXIDE MOIETY

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Chinese Journal of Polymer Science 2008年第6期26卷 793-797页

作者：唐旭东 College of Material Science & Chemical Engineering Tianjin University of Science & Technology

Aromatic copolyamides were synthesized by the Yamazaki phosphorylation method starting from bis(4- carboxyphenyl) phenyl phosphine oxide,terephthalic acid and 4,4 -diaminodiphenyl *** copolymers with inherent viscosities of 0.52-0.99 dL/g were *** structures of the copolyamides were characterized by elemental analysis, FTIR and *** glass transition temperatures were measured by DSC and DMA,respectively,and the results showed that the T_gs of the polymers were higher than 287℃.thermal de...

关键词： Aromatic polyamide Phosphorylation BCPPO Solubility thermal stability.

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SYNTHESIS AND CHARACTERIZATION OF NOVEL OPTICALLY ACTIVE POLY(AMIDE-IMIDE)S AND POLY(ESTER-IMIDE)S CONTAINING CALIX[4]ARENE AND AMINO ACID UNITS WITH BINDING ABILITY TOWARDS ALKALI METAL AND TOXIC HEAVY METAL CATIONS

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Chinese Journal of Polymer Science 2010年第5期28卷 731-743页

作者： Abdol-reza Hajipour Sakineh Habibi Arnold E.Ruoho Dept.of Pharmacology University of WisconsinMedical SchoolMadison53706-1532WIUSA Pharmaceutical Research Laboratory College of ChemistryIsfahan University of TechnologyIsfahan 84156IR Iran

A novel calix[4]arene derivative 2 with amino functional groups at the lower rim was first prepared via introduction of nitro functional groups and amination of the dinitro derivative of calix[4]arene. The optically active monomers were synthesized by dehydration of L-leucine （and L-isoleucine） and 3,3＇,4,4＇-benzophenonetetracarboxylic- 3,3＇,4,4＇-dianhydride （3） followed by reaction with thionyl chloride to form 5a and 5b. Two methods, polymerization under microwave irradiation and solution polymerization in CH2Cl2/TEA, were then employed to carry out the condensation polymerization of 2 with the optically active monomers 5a and 5b, respectively. The polymerization conditions affected the kind of resulting polymers, poly（amide-imide）s （PAIs） 6a and 6b and poly（ester-imide）s （PEIs） 6a＇ and 6b＇ were obtained selectively in good yields and moderate inherent viscosities. Sorption-extraction experiments were carried out using cram picrate extraction method and verified good binding ability of the resulting calixarene-based polymers towards silver, alkali metal and toxic heavy metal cations. Also thermogravimetric analysis indicated that the resulting PAIs and PEIs were thermally stable.

关键词： Condensation polymerization Ionophores Optically active Toxic heavy metals Polymeric calixarenes thermal stability.

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