PE,EVA及LDPE／EVA共混物辐照特性的研究

本文在对乙烯－醋酸乙烯共聚物（ＥＶＡ）和聚乙烯（ＰＥ），低密度聚乙烯（ＬＤＰＥ）、线性低密度聚乙烯（ＬＬＤＰＥ）及高密度聚乙烯（ＨＤＰＥ）在＾６０Ｃｏγ射线辐照前后的性能进行比较的基础上，着重研究了ＬＤＰＥ／ＥＶＡ共混物在＾６０Ｃｏγ射线辐照前后的拉伸性能和交联度的变化，以及ＥＶＡ添加量、ＶＡ含量及熔体流动速率（ＭＦＲ）对这些变化的影响。     

PVF2／P（MM—St）共混体系的结晶性能和相容性的研究

用示差量热法（ＤＳＣ）、动态力学分析法（ＤＭＡ）和悬浮法测密度法研究了聚偏氟乙烯（ＰＶＦ２）／甲基丙烯酸甲酯与苯乙烯的无规共聚和［Ｐ（ＭＭＡ－Ｓｔ）］的共混体系的相容性和结晶性能。结果发现ＰＶＦ２／Ｐ（ＭＭＡ－Ｓｔ）共混体系是部分相容体系,其结晶性能随共混物中Ｐ（ＭＭＡ－Ｓｔ）的含量而变化,并就模压成型的热历史对该共混体系相容性的影响进行了讨论。     

氯醚橡胶/氯化聚乙烯共混物的性能研究

考察了共混比、硫化体系、高耐磨炉黑（ＨＡＦ）及润滑剂二硫化钼的用量对氯醚橡胶／氯化聚乙烯（ＣＯ／ＣＰＥ）共混物性能的影响,结果表明：ＣＯ中混入ＣＰＥ后硬度增大,而综合性能较好;采用促进剂ＮＡ２２／四氧化三铅硫化体系,促进剂ＮＡ２２为１份时,共混物具有较好的综合性能;当ＨＡＦ用量为４５份时,共混物的拉伸强度及撕裂强度最佳;当润滑剂二硫化钼用量为２～４份时,共混物具有较好的综合性能。用差示扫描量热仪和扫描电子显微镜研究了共混物的形态及相容性,发现ＣＯ／ＣＰＥ是一个热力学相容体系     

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     

聚丙烯熔融接枝马来酸酐的研究

研究了聚丙烯熔融接枝顺丁烯二酸酐（ＭＡＨ）过程中ＭＡＨ的均聚、支化和过氧化二异丙苯（ＤＣＰ）分解速率等问题，用同向双螺杆挤出机，在固定螺杆转速下。考察了ＭＡＨ、ＤＣＰ加入量和挤出温度对接枝聚合物中游离酸酐含量、接枝率及ＭＦＲ的影响，并初步研究了游离酸酐对反应性共混物ＲＰＳ／ＰＰ－ｇ－ＭＡＨ拉伸性能的影响。     

EVA改性PE共混物力学性能和流变性能的研究

讨论了橡塑共混比、填料用量等因素对乙烯－醋酸乙烯共聚物（ＥＶＡ）改性ＰＥ共混物力学性能和流变性能的影响。试验结果表明，ＥＶＡ弹性体的加入降低了共混物的拉伸强度，提高了扯断伸长率及共混物熔体的流动性；活性碳酸钙的加入使共混物的拉伸强度、扯断伸长率和流动性下降；ＨＤＰＥ的加入提高了共混物的拉伸强度，但扯断伸长率和流动性下降。     

含TLCP的PET共混纤维结构和性能

以热致性液晶共聚酯——聚对苯二甲酸乙二酯／对羟基苯甲酸（ＰＥＴ／ＰＨＢ）作为添加剂与ＰＥＴ共混纺丝，研究该ＰＥＴ／ＴＬＣＰ（热致性液晶高聚物）共混物的可纺性，并用ＤＳＣ、Ｘ光衍射、声速和应力－应变等方法对纤维的热性能、结晶和取向结构以及力学性能进行了表征。结果表明，ＴＬＣＰ质量含量为５％左右的ＰＥＴ共混物可纺性良好。ＴＬＣＰ对ＰＥＴ从熔体结晶具有阻止作用，共混初生纤维的玻璃化转变和冷结晶温度均因ＴＬＣＰ的存在而升高。ＴＬＣＰ质量含量为５％的共混物纤维结晶结构与纯ＰＥＴ纤维相似，但晶粒尺寸较小，且晶粒尺寸大小与共混物组成、喷丝头拉伸比和后拉伸比有关。ＴＬＣＰ含量增加，共混纤维取向度和模量增大，而强度下降，但后拉伸可使纤维强度有较大的提高。     

动态硫化了腈橡胶／酚醛树脂共混型热塑性弹性体性能的研究

用动态硫化法制备了丁腈（ＮＢＲ）／酚醛树脂（ＰＦ）共混型热塑性弹性体。研究了ＮＢＲ中丙烯腈含量、ＰＦ品种、橡塑并用比和硫化体系对共混物性能的影响。研究结果表明：随ＮＢＲ中丙烯腈含量的增加，共混物的强度有所提高；随ＰＦ用量的增加，共混物的拉伸强度显著提高，耐油性能和老化性能均得到明显提高：硫磺硫化体系可使ＮＢＲ／ＰＦ并用体系硫化胶有较好的物理机械性能。     

聚氯乙烯与热塑性聚氨酯的共混改性

将聚氯乙烯（ＰＶＣ）与自制的热塑性聚氨酯（ＴＰＵ）进行共混改性，试验研究了ＰＶＣ分子量、ＰＶＣ／ＴＰＵ共混比及共混方法对共混物性能的影响。结果表明，ＸＳ－３型ＰＶＣ与ＴＰＵ的相容性最好，性能也较为满意。     

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     

Processing morphology of PVC/MBS blend

MBS resin, an impact modifier for PVC, plays an important role in PVC processing, the details of which, however, are not well understood. The use of a temperature programmable Brabender Plasticorder and new microscopic techniques have revealed that MBS inhibits the comminution of PVC grain in the initial stage of processing, and PVC breakdown occurs after the MBS melts. Dynamic melting of MBS is observed as a Brabender torque peak. These characteristics of PVC/MBS blends are quite different from those of PVC/processing aid blends. Processing features of PVC/MBS blends are reported and compared with those of PVC/processing aid blends.     

A Study of the Viscoelastic and Rheological Properties of PVC/CPE Blends Modified by Using Polylauryllactam

Abstract

Polylauryllactam was used to improve the impact strength of polyvinylchloride (PVC)/chlorinated polyethylene (CPE) blends without sacrificing their tensile properties. The enhancement of the impact strength increased with the increase of the CPE content in the PVC/CPE blends due to the formation of intermolecular hydrogen bonds among PVC, polylauryllactam and CPE macromolecules. A doubled impact strength of the PVC/CPE blend with 20 weight percent of CPE was obtained after the addition of 1.5 phr polylauryllactam. The PVC/CPE blends with polylauryllactam have a better dimensional stability compared with the PVC/CPE blends without the additive, according to their viscoelastic characteristics. Polylauryllactam shortened the processing time to reach a minimum melt viscosity in the processing of the PVC/CPE blends.     

Mechanical Properties and Morphology of Recycled. Plastic Wastes by Solution Blending

In this study, bottles of mineral water and yogurt as well as Styrofoam bowls were recycled and identified by infrared spectroscopy as poly(vinyl chloride) (PVC), high-impact polystyrene (HIPS), and polystyrene (PS). Solution blending was employed to make polymer blends from these recycled plastics, including PVC/PS, PVC/HIPS/PS blends, and PVC/HIPS blends with or without a com-patibilizer, styrenelp-chlorostyrene (ST-CMS). Thermal behavior from differential scanning calorimetry was used to examine the compatibility of the blends. For the PVC/PS and PVC/HIPS/PS systems, it is found that although the third component (HIPS) may not be good enough as a compatibilizer, the addition of HIPS to the two-component blend (PVC/PS) may enhance the mechanical properties at the specific composition, especially for the blends at the intermediate concentrations. For PVC/HIPS blends with the ST-CMS copolymer as a compatibilizer, all the mechanical properties of the blends except the elongation at break, in general, increased with increasing the concentration of compatibilizer due to the increase of compatibility. The abnormal fracture strain was attributed to the differences in adhesion when various amounts of ST-CMS was added. The results of mechanical properties of the blends were consistent with the morphology from scanning electron microscopy.     

Thermal and mechanical properties of electron beam irradiated poly(vinyl chloride)/polystyrene blends

The effect of electron beam irradiation on the thermal and mechanical properties of poly(vinyl chloride)/polystyrene (PVC/PS) blends and PVC/PS blends containing epoxidized natural rubber (ENR) was studied. The thermogravimetric analysis study showed that the thermal decomposition of the plasticized PVC individual polymer goes through two stages, whereas PS decomposes through one stage. However, the temperature of the maximum rate of reaction (T_max) of PS is much higher than that for PVC and their blends. Meanwhile, the T_max was found to increase with increasing PS ratios in the blend. The thermal stability of PVC/PS blends was greatly increased after electron beam irradiation in comparison with unirradiated blends. Moreover, the addition of ENR to PVC/PS increased the thermal stability. On the other hand, the mechanical properties in terms of tensile strength and elongation at break of PVC/PS blends are lower than pure PVC polymer because of the immiscibility. However, the addition of ENR to the PVC/PS (80/20) blend increased the elongation at break from 114 to 321% associated with a small effect on the tensile properties. These behaviors were supported by structure morphology studies observations, which indicate an improvement in the interfacial adhesion between the phases. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers     

Preparation and Properties of Volume Expansion Type Blends of Plasticized Polyvinyl Chloride/Starch Graft Polyacrylate Sodium

A series of water-swellable elastomers were prepared by blending plasticized polyvinyl chloride (PVC) with starch graft polyacrylate sodium (SZ_A). The morphology and properties of PVC/SZ_A blends were studied by means of water absorbing ratio, water swelling ratio, weight loss ratio, tensile stress-strain and SEM tests. The results indicate that when PVC/SZ_A blends were pretreated by means of soaking in distilled water, SZ_A, which weakly interacts with the PVC matrix can be washed out. After the pretreatment, the blends were quite stable in water, the water absorbing ratio of the blends increased and the water swelling ratio of the blends nearly was unchanged in the further water absorbing tests. The mechanical properties of the pretreated blends slightly reduced as compared to those of the without pretreatment. With plasticizer content of the plasticized PVC in the blends, the water absorbing ratio and the water swelling ratio increased.     

Toughness,dynamic mechanical property,and morphology of polyvinylchloride/acrylonitrile‐styrene‐butyl acrylate blends

Acrylonitrile‐styrene‐butyl acrylate (ASA) graft copolymers with different acrylonitrile (AN) contents, the core‐shell ratio, and tert‐dodecyl mercaptan (TDDM) amounts were synthesized by seed emulsion polymerization. Polyvinylchloride (PVC)/ASA blends were prepared by melt blending ASA graft copolymers with PVC resin. Then the toughness, dynamic mechanical property, and morphology of the PVC/ASA blends were investigated. The results indicated that the impact strength of the PVC/ASA blends increased and then decreased with the increase of the AN content in poly(styrene‐co‐acrylonitrile (SAN) copolymer, and increased with the increase of the core‐shell ratio of ASA. It was shown that brittle‐ductile transition of PVC/ASA blends was dependent on poly(butyl acrylate) (PBA) rubber content in blends and independent of AN content in SAN copolymer. The introduction of TDDM made the toughness of PVC/ASA blends poor. Dynamic mechanical analysis (DMA) curves exhibited that PVC and SAN copolymers were immiscible over the entire AN composition range. From scanning electron microscopy (SEM), it was found that the dispersion of ASA in PVC/ASA blends was dependent on the AN content in SAN copolymer and TDDM amounts. J. VINYL ADDIT. TECHNOL., 22:43–50, 2016. © 2014 Society of Plastics Engineers     

3D打印用聚氯乙烯多相复合体系的开发

采用高分子类增塑剂乙烯-乙酸乙烯酯共聚物(EVM)替代聚氯乙烯(PVC)传统增塑剂,制备出具有双连续相结构的PVC/EVM/聚乳酸(PLA)共混物.通过热分析、流变学测试及微观形貌观察等研究了共混物结构与性能间的关系.结果表明,随着填料蒙脱土(OMMT)或碳纳米管的加入,PVC/EVM/PLA共混物的热分解温度和体系燃...     

Compatibility of poly(vinyl chloride) and polyurethane blends

The compatibility and the mechanical properties of the blends of polyurethane (PU) elastomer and poly(vinyl chloride) (PVC) were studied. The results showed partial compatibility between PU and PVC. When the portion of PVC in blends exceeded 75%, the compatibility decreased. On the other hand, increasing the molecular weight of the glycol in PU improved the compatibility. The elongation decreased and the Young's modulus increased as the proportion of the weight of PVC in blends was increased. The tensile strength reached a minimum when PU/PVC was 50/50.     

乳化剂对合成MBS树脂和PVC/MBS合金力学性能的影响

通过调节乳化剂十二烷基苯磺酸钠（SDBS）的用量合成MBS树脂，并将其与聚氯乙烯（PVC）树脂进行共混，测试PVC／MBS合金的力学性能。测试结果表明：乳化剂的用量越多，MBS树脂相的相对分子质量越低，PVC／MBS合金的拉伸强度变化不明显，其冲击强度先增大后减小。     

己二酸锌钙皂纳米氧化铈/氧化镧对PVC/ASA的热稳定作用

合成了己二酸锌钙皂,并将纳米氧化铈和氧化镧分别作为共稳定剂制备了新型复合热稳定剂。采用刚果红法、热失重分析仪、动态力学分析仪等考查了复合热稳定剂对聚氯乙烯/丙烯酸酯苯乙烯丙烯腈接枝共聚物（PVC/ASA）共混材料的热稳定效果及动态力学性能。结果表明,稀土化合物作为共稳定剂可以提高己二酸锌钙皂对PVC/ASA共混材料的热稳定效果,氧化镧与己二酸锌钙皂的协同效果优于纳米氧化铈,而纳米氧化铈的加入可以提高材料的热变形温度。