四亚乙基五胺对PVC和PVC/NBR共混物的交联作用

从硫化特性、热变形值、凝胶质量分数和物理性能等方面考察了四亚乙基五胺（ＴＥＰＡ）对ＰＶＣ和ＰＶＣ／ＮＢＲ共混物的交联作用以及ＰＶＣ和ＮＢＲ同时交联对共混物性能的影响。结果表明,ＰＶＣ／ＮＢＲ共混物中的ＰＶＣ组分交联后,共混物的物理性能和热变形性能都有所改善;ＰＶＣ和ＮＢＲ两组分同时交联可改善共混物的物理性能和热变形性能,在ＮＢＲ用量较大（６０份以上）时效果更为明显,若ＮＢＲ用量太低,则共混物热变形性能反而有所下降;交联剂ＴＥＰＡ对硫黄硫化ＮＢＲ有一定抑制作用,对共混物的物理性能影响不大,但在一定用量范围内有较小的劣化作用     

动态硫化PVC/SBR共混体系的研究

采用动态硫化法制备了ＰＶＣ／ＳＢＲ共混物，考察了橡塑比、硫化体系、相容剂及ＰＶＣ交联对共混物性能的影响。结果表明，当ＰＶＣ／ＳＢＲ并用比为７５／２５，相容剂ＮＢＲ／氯化聚乙烯并用比为２．５／２．５，采用半有效或半有效加２份交联剂ＤＣＰ的硫化体系时，共混物综合性能较好。在ＰＶＣ中加入０．４份促进剂ＮＡ－２２可明显改善共混物的压缩永久变形。     

HPVC/SBR共混体系相容性的研究

采用动态硫化方法制备高聚合度聚氯乙烯（ＨＰＶＣ）／ＳＢＲ共混型热塑性弹性体,考察了单一组分相容剂「相容剂分别为ＮＢＲ２７０、ＮＢＲ Ｐ６５、ＣＰＥ和氢化苯乙烯－丁二烯、苯乙烯嵌段共聚物（ＳＥＢＳ）」、复合相容剂（ＳＥＢＳ／ＮＢＲ和ＣＰＥ／ＮＢＲ）及交联程度对ＨＰＶＣ／ＳＢＲ共混体系相容性的影响。结果表明,使用复合相容剂可明显改善ＨＰＶＣ／ＳＢＲ共混物的性能;动态硫化在改善共混物力学性能方面起主要作     

热塑性酚醛树脂/丁腈橡胶共混物性能的研究

采用差示扫描量热法（ＤＳＣ）、红外光谱法和力学性能测试等方法，研究了一系列配比的热塑性酚醛树脂（ＰＦ）／丁腈橡胶（ＮＢＲ）共混物的性能。共混比为（３—５０）／１００的ＰＦ／ＮＢＲ共混物表现出最佳的力学性能。ＤＳＣ分析表明六亚甲基四胺固化ＰＦ和硫黄硫化ＮＢＲ是共混物硫化过程中的主导反应，但红外分析表明ＮＢＲ中—ＣＮ与ＰＦ发生了化学反应，这种反应正是共混物获得良好性能的原因。     

PVC／ENR／XNBR（NBR）动态硫化共混物

能干不氧化天然橡胶（ＥＮＲ）、聚氯乙烯（ＰＶＣ）和羧基丁腈橡胶（ＸＮＢＲ）之间的自硫化反应，实现了ＰＶＣ／ＥＮＲ／ＸＮＢＲ三元共混物的动态友化，由此得到了具有热塑性弹性体的一些典型特征的ＰＶＣ／ＥＮＲ／ＸＮＢＲ动态自硫化共混物。该人混物与自硫化反应不明显的ＰＶＣ／ＥＮＲ／ＮＢＲ共混物进行了比较，发现动态自硫化反应显著提高了共混物的综合性能。结果表明，当橡塑比为７０／３０时，前者的拉伸强度为１１．８     

EVM/NBR动态硫化共混物性能的研究

研究了橡胶型乙烯醋酸乙烯酯共聚物（ＥＶＭ）／ＮＢＲ共混比、硫黄和叔丁基酚醛树脂（２４０２树脂）硫化体系对共混物性能的影响，并对比了动态硫化和静态硫化共混物在性能上的差异。试验结果表明，ＥＶＭ／ＮＢＲ共混比显著影响共混物的力学性能，而采用ＮＢＲ预先动态硫化的方法后，共混物胶料的挤出口型膨胀率明显减小，老化性能得到改善，同时减弱了硫黄和２４０２树脂等硫化体系对ＥＶＭ硫化的影响，使多种硫化体系可以共存于共混物中。ＤＳＣ分析表明ＥＶＭ／ＮＢＲ动态硫化共混物只有一个玻璃化温度，且介于ＥＶＭ和ＮＢＲ之间，说明ＥＶＭ和ＮＢＲ具有良好的相容性。     

HDP—PVC／ABS合金材料的研究

研究了高聚合度聚氯乙烯（ＨＤＰ－ＰＶＣ）／ＡＢＳ二元体系力学性能以及添加第三组分对合金材料力学性能的影响。结果表明：ＨＤＰ－ＰＶＣ／ＡＢＳ配比为１００／２５时,共混物的综合性能好,体系能形成较完善的海岛结构;ＨＤＰ－ＰＶＣ／ＡＢＳ／ＭＢＳ体系中,ＭＢＳ能改善多元体系的界面性能,提高合金材料的综合性能;ＨＤＰ－ＰＶＣ／ＡＢＳ／ＣＰＥ体系中,ＣＰＥ能使形成网状结构和海岛结构共存的合金体系,提高合金材料     

NBR／EPDM共混橡胶

ＮＢＲ／ＥＰＤＭ共混橡胶《弹性体》１９９３，№１报导，北京化工学院利用商品化高聚物ＥＶＡ－１４作增容剂，制得了优异机械性能的ＮＢＲ／ＥＰＤＭ共混胶。胶料配方为：ＮＢＲ６０，ＥＰＤＭ３０，ＥＶＡ－１４１０，ＨＡＦ３０，ＤＢＰ１０，防ＲＤ１．０，ＺｎＯ５...     

天然橡胶/氯醚橡胶/相容剂共混物的研究

利用差示扫描量热法（ＤＳＣ）和相差显微镜（ＰＤＭ）对氯化聚乙烯（ＣＰＥ）、丁腈橡胶（ＮＢＲ２６）和环氧化天然橡胶（ＥＮＲ５０）作天然橡胶／氯醚橡胶（ＮＲ／ＥＨＲ）体系的相容剂进行了研究。通过考察共混胶的力学性能，确定了相容剂的适宜用量和共混时间。结果表明，ＣＰＥ，ＮＢＲ２６和ＥＮＲ５０能有效提高ＥＨＲ在ＮＲ中的分散程度，混炼时间１５ｍｉｎ，用量１０—１５份为宜。     

聚氯乙烯／环氧化天然橡胶共混型热塑性弹性体的配方研究

重点研究环氧化天然橡胶（ＥＮＲ）的环氧化程度，ＰＶＣ／ＥＮＲ配比，硫化体系（交联剂及共交联剂），填充补强体系以及增塑剂对ＰＶＣ／ＥＮＲ共混型热塑性弹性体物理性能的影响。结果表明当ＥＮＲ的环氧化程度为５０ｍｏｌ％，ＰＶＣ／ＥＮＲ＝５０／５０，采用ＤＣＰ作交联剂，硫黄作共交联剂，在ＥＮＲ中充入适量的重质芳烃油，通过适宜的工艺条件和动态硫化方式，可制出力学性能较好的ＰＶＣ／ＥＮＲ共混型ＴＰＶ。     

亚乙基硫脲对PVC和PVC/ENR共混物的交联作用

从交联速率、压缩永久变形、凝胶质量分数、强伸性能和耐热性能等方面考察了亚乙基硫脲（ＥＴＵ）和ＥＴＵ／硫黄对ＰＶＣ及其与环氧化天然橡胶（ＥＮＲ）共混物的交联作用。结果表明,ＥＴＵ和ＥＴＵ／硫黄对ＰＶＣ及其与ＥＮＲ的共混物有明显的交联作用;交联后共混物的物理性能和耐热性能均有较大提高;适当增大ＥＮＲ用量,有利于提高共混物的热变形性能;ＰＶＣ／ＥＮＲ的共混比为７０／３０时,硫黄的最佳用量为１５份,促进剂选择促进剂ＤＭ／ＴＭＴＤ体系为佳。     

Application of phase dispersion–crosslinking synergism on recycling commingled plastic wastes

A tetra‐component blend, consisting of low‐density polyethylene (LDPE), polyvinyl chloride (PVC), polypropylene (PP), and polystyrene (PS), was studied as a model system of commingled plastic wastes (LDPE/PVC/PP/PS, mass ratio: 70/10/10/10). Effects of chlorinated polyethylene (CPE), ethylene–propylene–diene monomer (EPDM), styrene–butadiene–styrene (SBS), and their mixture (CPE/EPDM/SBS, mass ratio: 2/2/2) on the mechanical properties and morphology of the system were investigated. With addition of several elastomers and their mixture, the tensile strength of the blends decreased slightly, although both the elongation at break and the impact strength increased. Among these elastomers, EPDM exhibited the most significant impact modification effect for the tetra‐component blends. SBS and the mixture have a good phase‐dispersion effect for the tetra‐component blend. By adding a crosslinking agent [dicumyl peroxide (DCP)], the mechanical properties of the tetra‐component blends also increased. When either SBS or the mixture was added to the blend together with DCP, the probability that the crosslinking agent (DCP) would be at the interface improved because of the phase‐dispersion effect of SBS. Therefore, more co‐crosslinked products will form between LDPE and other components. Accordingly, remarkable improvement of the interfacial adhesion and hence the mechanical properties of the tetra‐component blends occurred. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2947–2952, 2001     

不同分子链结构聚乙烯的交联研究

研究了线性、短支链和长支链支化三种分子链结构聚乙烯的化学交联过程,对交联体系的机械性能和热性能进行了分析对比。结果表明,在同样交联剂含量情况下,聚乙烯交联体系的凝胶含量顺序是:长支链支化>短支链支化>线性结构;交联引起的拉伸强度变化率为长支链支化>短支链支化>线性结构;交联引起的断裂伸长率变化率为线性结构>短支链支化>长支链支化;交联引起结晶度的下降程度为线性结构>短支链支化>长支链支化。     

VC／BA共混物增容PVC／HDPE共混体系的研究

采用氯乙烯—丙烯酸丁酯(VC/BA)共混物作为聚氯乙烯(PVC)/高密度聚乙烯(HDPE)共混物的增容剂,通过冲击实验、拉仲实验、动态力学分析,系统地研究了共混体系性能与其结构之间的关系。通过Brabender流变仪测定了VC/BA共混物增容PVC/HDPE共混体系的流变性能。结果表明,VC/BA共混物是PVC/HDPE共混体系的良好增容剂。在一定范围内,VC/BA共混物与HDPE对PVC有协同增韧效应。vC/BA和HDPE的加入改善了PVC的塑化和流变性能     

HDPE/LDPE复合交联物的热降解研究

采用热重分析仪（TG）考察了高密度聚乙烯（HDPE）／低密度聚乙烯（LDPE）复合交联物的热稳定性。结果显示，HDPE／LDPE复合交联物的热稳定性低于HDPE／LDPE共混物。FTIR分析证实，交联反应使聚乙烯（PE）的支化程度提高，取代基的位阻效应在一定程度上影响了PE的热降解过程。在N2气氛下，HDPE／LDPE共混物及交联物的热降解过程均为一步降解反应。Kissinger法求解HDPE／LDPE共混物及其复合交联物的热降解活化能发现，LDPE质量分数在20％～30％之间变化时，HDPE／LDPE交联物的热降解过程对温度的敏感性发生了突变。     

Self‐crosslinking and cocrosslinking with nitrile rubber of poly(vinyl chloride) with pendent N,N‐diethyldithiocarbamate group

In order to realize the self‐crosslinking and cocrosslinking of poly(vinyl chloride) (PVC) with nitrile‐butadiene rubber (NBR), PVC with pendent N,N‐diethyldithiocarbamate groups (PVC‐SR) was prepared from the reaction of PVC with sodium SR in butanone. The PVC‐SR was self‐crosslinked and the PVC‐SR/NBR blend was cocrosslinked under heating at 170°C. The effect of the degree of functionality of PVC‐SR on the torque, gel content, glass‐transition temperature, and tensile properties was investigated. The results showed that the crosslinking reaction did not occur for PVC, NBR, or the PVC/NBR blend. Introducing the SR groups into PVC caused the crosslinking reaction to occur and the high gel contents of the crosslinked samples were obtained in 15 min. The degree of crosslinking increased with the degree of functionality of PVC‐SR. The mechanism of the crosslinking reaction was discussed. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 634–638, 2001     

Phase dispersion–crosslinking synergism in binary blends of poly(vinyl chloride) with low‐density polyethylene: Entrapping phenomenon in PVC/LDPE/DCP blend

The co‐crosslinked products and the entrapping phenomenon that may exist in a poly(vinyl chloride)/low density polyethylene/dicumyl peroxide (PVC/LDPE/DCP) blend were investigated. The results of selective extraction show that unextracted PVC was due to not being co‐crosslinked with LDPE but being entrapped by the networks formed by the LDPE phase. SBR, as a solid‐phase dispersant, can promote the perfection of networks of the LDPE phase when it is added to the PVC/LDPE blends together with DCP, which leads to more PVC unextracted and improvement of the mechanical properties of PVC/LDPE blends. Meanwhile, the improvement of the tensile properties is dependent mainly on the properties of the LDPE networks. Finally, the mechanism of phase dispersion–crosslinking synergism is presented. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1296–1303, 2003     

Radiation crosslinking of poly(vinyl chloride) with trimethylolpropanetrimethacrylate. IV. Effect of diundecyl phthalate: Dependence of physical properties on composition

Blends of poly(vinyl chloride) (PVC) with polyfunctional monomers may be crosslinked by ionizing radiation. The physical properties of PVC blended with trimethylolpropanetrimethacrylate (TMPTMA) and diundecyl phthalate (DUP) were studied. The TMPTMA monomer crosslinked the blend by homopolymerization and/or grafting to PVC. The plasticizer, DUP, was chemically inert under irradiation but, by plasticizing the macromolecules and diluting the monomer, changed the kinetics extensively. Characteristics of the glass transitions and the tensile mechanical properties have been correlated with blend composition and radiation dose. Before irradiation, poly(vinyl chloride) was plasticized by both DUP and TMPTMA monomer. The increase in glass transition temperature and mechanical strength following irradiation to 5 Mrad was correlated with the TMPTMA content of the blend. Both the molecular structure of the network and the DUP content of the blend were factors in determining the physical properties of the final crosslinked blend. The molecular structure was determined by the kinetics of the crosslinking reactions, which in turn were determined by the blend composition. A molecular interpretation consistent with the physical properties, chemical kinetics, and mechanism of the crosslinking system has been presented.     

填料对聚氯乙烯电缆料辐射交联的影响

研究了陶土、Ａｌ（ＯＨ）３、ＣａＣＯ３等三种不同填料对软质聚氯乙烯（ＰＶＣ）电缆料辐射交联的影响,交联剂为三甲氧基丙烷三甲基丙烯酸酯（ＴＭＰＴＭＡ）,由Ｃｏ＾６０γ射线辐照至４．０Ｍｒａｄ。结果表明,填料的加入使ＰＶＣ辐射交联后凝胶含量下降。在相同加入量下,加入ＣａＣＯ３使凝胶含量下降最多,加入Ａｌ（ＯＨ）３次之。与不加填料相比,加入三种填料后均使ＰＶＣ辐射交联后力学性能降低。     

紫外光辐照交联聚氯乙烯的研究

研究了聚氯乙烯(PVC)在增塑剂邻苯二甲酸二辛酯(DOP)存在的情况下,以二苯甲酮(BP)为光敏剂、三丙烯酸三羟甲基丙烷酯(TMPTA)为交联剂的紫外光辐照交联。实验证明:光敏剂对交联有着显著的影响;经过辐照,可大幅度提高PVC制品的硬度及拉伸强度。