刚性有机粒子对PVC／CPE共混体加工和力学性能的影响

本文用Ｂｒａｂｅｎｄｅｒ塑化仪，双锟开炼机研究了刚性有机粒子对ＰＶＣ／ＣＰＥ共混体熔融塑化为及力学性能的影响，探讨了不同加工温度对ＰＶＣ／ＣＰＥ共混体力学性能的影响，实验表明：添加少量刚性有机粒子后，体系的塑化时间缩短，塑化行为改善，韧性有较大幅度提高，拉伸强度有所改善，加工温度为１６０－１８０℃体系性能最好。     

HIPS对没PVC体系的改性研究

研究了刚性有机粒子ＨＩＰＳＤ对不同改性ＰＶＣ体系力学性能的影响。结果表明,对于改性ＰＶＣ／ＰＥ－Ｃ基体添加少量的ＨＩＳＰ后,共混体系塑化行为改善,缺口冲击度明显提高,拉伸强度下降不大;而对于改性ＰＶＣ和改性ＰＶＣ／ＭＢＳ基体,共混体系的力学性能没有提高,且有负面影响。     

SAN与ABS增韧改性聚氯乙烯的研究

通过ＡＢＳ用量变化调节ＰＶＣ／ＡＢＳ基体的韧性，研究了刚性聚合物ＳＡＮ对ＰＶＣ／ＡＢＳ共混体系力学性能的影响，并讨论了ＳＡＮ对不同二元基体ＰＶＣ／ＣＰＥ改性效果的影响。     

反应挤了HDPE／PET共混合金结构与性能研究

采用ＤＳＣ、ＷＡＸＤ、ＳＥＭ及ＴＧＡ等方法研究了ＨＤＰＥ／ＰＥＴ共混合金在增溶剂Ｅ／ＶＡＣ或Ｅ／ＡＡ作用下的结晶性、形态结构及热稳定性。结果表明，Ｅ／ＶＡＣ或Ｅ／ＡＡ的加入，使ＨＤＰＥ／ＰＥＴ体系中ＨＤＰＥ组分的熔融热焓降低，结晶度下降，但熔融峰位置和晶胞基本保持不变；从ＳＥＭ照片可以观察到Ｅ／ＶＡＣ、Ｅ／ＡＡ对共混体系具有一定的增容作用，Ｅ／ＡＡ和效果优于Ｅ／ＶＡＣ；共混体系的热稳定性随Ｅ／ＶＡ     

聚α-甲基苯乙烯对PVC/CPE和废旧PVC/PE/CPE共混体系力学性能影响的研究

研究了加工流动改性剂聚α－甲基苯乙烯（ＡＭＳ）对软质ＰＶＣ／ＣＰＥ和废旧软质ＰＶＣ／废旧ＰＥ／ＣＰＥ共混体系力学性能的影响,并探讨了ＡＭＳ的作用机理。还研究了废ＩＨＰＳ泡沫塑料对废旧软质ＰＶＣ／废ＩＨＰＥ／ＰＳ共混体系力学性能的影响。     

PVC／CPE／AS共混工艺及其力学性能研究

研究了ＰＶＣ／ＣＰＥ／ＡＳ的共混工艺及力学性能。结果表明，在一定的工艺条件下，向ＰＶＣ中添加少量的刚性聚合物ＡＳ与弹性体ＣＰＥ的混合物，可使共混材料的站击强度有较大幅度的提高。     

HIPS对不同PVC体系的改性研究

研究了刚性有机粒了ＨＩＰＳ对不同改性ＰＶＣ体系力学性能的影响。结果表明，对于改性ＰＶＣ／ＰＥ－Ｃ基体，添加少量的ＨＩＰＳ后，共混体系塑化行为改善，缺口 冲击强度明显的提高，拉伸强度下降不大；而对于改性ＰＶＣ和改性ＰＶＣ／ＭＢＳ基体，共混体系的力学性能没有提高，且有负面影响。     

SAN对PVC／CPE加工行为的影响

采用Ｂｒａｂｅｎｄｅｒ塑化仪和双辊开炼机，研究了几种刚性有机填料ＳＡＮ（苯乙烯和丙烯腈的共聚物）对ＰＶＣ／ＣＰＥ（聚氯乙烯／氯化聚乙烯）共混体加工行为及力学性能的影响。实验表明：这几种ＳＡＮ均有缩短ＰＶＣ／ＣＰＥ塑化时间，改善熔融塑化行为的效能，但不同流动性的ＳＡＮ作用有所差异。还证实了不同加工方法的改性效果不尽相同。     

PVC／LLDPE／EVA／交联剂共混体系中增容－交联协同作用的研究

本文讨论了ＰＶＣ／ＬＬＤＰＥ共混体系中，ＥＶＡ、交联剂对共混物力学性能、相形态的影响。ＥＶＡ作增容剂，能与交联剂发生协同作用，改善ＰＶＣ、ＬＬＤＰＥ的两相分散性，增强两相粘接力，大幅度提高共混物的强度和韧性。     

PVC/PVDF/CPE共混体系研究

以ＣＰＥ作为ＰＶＣ／ＰＶＤＦ的增容剂,研究了ＰＶＣ／ＰＶＤＦ／ＣＰＥ三元共混新体系。对不同组成的共混物的物理机械性能进行测试,分析了讨论了ＰＶＤＦ／ＣＰＥ的增韧效果和机理。结果表明：ＣＰＥ对ＰＶＣ／ＰＶＤＦ共混体系有明显的增容作用,ＰＶＤＦ／ＣＰＥ并用对增韧ＰＶＣ有显著的协同效应。     

PVC/EVA共混物的研究

本文研究了混炼温度和时间对PVC/EVA共混物抗冲性能的影响,发现加入聚乙烯,共混体系的抗冲击强度能进一步提高.用TEM观察了PVC/EVA的形态结构,采用Brabender塑化仪和毛细管流变仪研究了共混物的塑化和熔体流变行为.通过计算机对实验结果进行二元线性回归,建立了共混物的熔体粘度与剪切应力和温度相关联的数学模型.     

Crosslinking of polyvinyl chloride by electron beam irradiation in the presence of ethylene–vinyl acetate copolymer

Electron beam (EB) irradiation of polyvinyl chloride (PVC) was carried out in the presence of three different ethylene–vinyl acetate copolymers (EVA). The mechanical properties of the original and irradiated blends were tested. The gel content measurement, chlorine loss upon electron irradiation, and gel permeation chromatograph (GPC) were used to characterize the effect of EVA on the irradiation behavior of PVC/EVA blends. The content and the chemical structure of EVA in the blends had considerable effects on the mechanical properties and gel content of the blends. The incorporation of EVA into PVC blend can increase the gel content and reduce chlorine loss of the blends. The GPC analysis of the soluble part in the irradiated PVC samples showed that the addition of EVA into the PVC blend lowered the polydispersity of molecular weight of PVC. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1571–1575, 2004     

辐照交联PVC／EVA共混物的形态结构与性能

以电子束为辐照源，以三羟甲基丙烷三丙烯酸酯（TMPTA）单体为交联敏化剂，对聚氯乙烯与乙烯－醋酸乙烯共聚物（EVA）的共混物进行辐照交联。采用红外吸收光谱、扫描电镜方法分析了添加改性EVA的共混物形态结构。通过凝胶含量、力学性能的测定，得到结论：EVA共聚物与PVC共混可以促进PVC辐照交联，改性EVA促进效果更明显；辐照剂量增大、体系凝胶含量增加，力学性能及热延伸性能提高，但辐射剂量高于5Mrad之后，体系降解程度明显增加。     

相容剂对PVC／PA6体系形态结构的影响

研究了SMA—g—MAH、SEBS—g—MAH和EVA—g—MAH3种相容剂对PVC／PA6共混物的增容效果。结果表明,未添加相容剂的PVC／PA6（100／20）共混物的相容性不好;添加SEBS—g—MAH和EVA—g—MAH两种相容剂后,PVC／PA6共混物的相容性得到一定程度的改善;添加SMA—g—MAH相容剂后,PA6很均匀地分散在PVC基体中。     

电子束辐照交联PVC/EVA共混物的研究

以丙烯酸酯类多官能团不饱和单体为交联敏化剂，采用电子束对聚氯乙烯(PVC)与乙烯—酸酸乙烯共聚物(EVA)的共混物进行辐照交联。研究了VA质量分数、交联敏化剂种类及用量、辐照剂量、EVA用量对共混物凝胶质量分数、力学性能以及热延伸性能的影响。结果表明：EVA共聚物能促进PVC的辐照交联，增加共混体系的凝胶质量分数，改善其力学及热延伸性能；EVA共聚物中VA质量分数增大，共混体系的凝胶质量分数增大，力学及热延伸性能改善更明显。     

Study on thermoplastic polyurethane/polypropylene (TPU/PP) blend as a blood bag material

Blends with different ratios of thermoplastic polyurethane/polypropylene (TPU/PP) were prepared by melt mixing using an internal Haake mixer. Properties of the blends were investigated using SEM micrographs of cryofractures and measurement of the mechanical strength, water absorption, cell culture, and platelet adhesion in vitro tests, which were compared with those of PVC blood bags. The effect of the addition of the ethylene–vinyl acetate (EVA) copolymer on the TPU/PP blend properties was investigated. The results indicated that a TPU/PP/EVA = 80/20/5 blend can be used as a new blood bag material. It was observed that the blend is homogeneous with higher mechanical strength than that of the commercial PVC blood bag. This blend also showed a compatible cell response in contact with L929 fibroblast cells and fewer tendencies to interaction with platelets compared to the PVC blood bag. Although the blends were immissible and no chemical reaction at the interface could be found, the blood compatibility of the blends were improved. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2496–2501, 2003     

Evaluation of mechanical properties and physical interactions of a ternary blend of poly(ethylene‐co‐octene)/poly(ethylene‐co‐vinyl acetate)/poly(vinyl chloride) in the molten state

In this work, ethylene‐co‐vinyl acetate (EVA), poly(ethylene‐co‐octene) (POE), and poly(vinyl chloride) (PVC) blends were processed in a molten state process using a corotating twin‐screw extruder to assess both the balance of mechanical properties and physical interactions in the melt state. Tensile measurements, scanning electron microscopy, and oscillatory rheometry were performed. By means of flow curves, the parameters of the power law as well as the distribution of relaxation times were assessed with the aid of a nonlinear regularization method. The mechanical properties for the EVA‐POE blend approximated the values for POE, while inclusion of PVC shifted the modulus values to those of neat EVA. The rise in modulus was corroborated by the PVC phase dispersion as solid particles that act as a reinforcement for the ternary blend. The rheological properties in the molten state show that the POE does not present molecular entanglement effects and so tends both to diminish the EVA mechanical properties and increase the fluidity of the blend. However, the addition of PVC both restored the EVA typical pseudoplastic feature and promoted the increase in the viscosity and the mechanical properties of the ternary blend. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Polymer-polymer interaction and modeling

The nature of intermolecular interaction in PVC/EVA system was investigated. Bathochromic shifts in infrared region revealed that not only EVA carbonyl but the ester group participates on interaction with PVC chain. These shifts were proportional to acetate content in the copolymer and the composition of EVA in the blend. The PVC group that effectively participates on interaction was not elucidated by infrared spectrometry, but molecular modeling of low molecular weight analogues indicated that hydrogen bonding is the most probable kind of intermolecular interaction present in this system. Received: 7 December 1996/Revised: 1 August 1997/Accepted: 7 August 1997