共查询到20条相似文献,搜索用时 78 毫秒
1.
2.
3.
梁焕强 《合成材料老化与应用》1985,(4)
按理,热稳定剂不单独使用,但通过对它们的特殊要求进行系统分析,加工者和配料者可以组成稳定剂体系,以提高加工性能,而且还对最终产品保持着一些保护作用。由于柔软性聚氯乙烯热稳定剂影响加工的许多方面,而且加工条件随加工的方法而变,因此要选择最佳的稳定剂或稳定剂体系是一个不容易的事情。如果你把产品性能要 相似文献
4.
5.
对比了无机铅盐与有机铅盐稳定剂的稳定性,并从共稳定剂、CPVC树脂含量以及加工工艺三个方面研究了CPVC复合铅体系的加工稳定性.结果表明,合适的共稳定剂可产生协同效应;添加适量的PVC树脂有利于CPVC的加工;加工工艺对CPVC的加工稳定化极其重要. 相似文献
6.
7.
8.
9.
稀土族定剂是一种无味、无毒、高效稳定剂,对PVC加工起很好的稳定作用。本文结合PVC压延加工实际,探讨了稀土稳定剂的应用特征,主为稀土稳定剂不失为替代有毒的重金属稳定剂的新型稳定剂品种,有广阔的开发应用前景。 相似文献
10.
在欧洲市场率先使用的一系列PVC有机热稳定剂,目前正销往北美市场。这些有机基热稳定剂(OBS),是美国康普顿(Crompton)公司于6年前为了帮助欧洲塑料管材加工厂商弃用铅类热稳定剂,而专门开发的环保型热稳定剂新品种,最初设计用于PVC硬制品的加工方面,最近已开始应用于软制品加工 相似文献
11.
12.
Frantiek Rybnik 《应用聚合物科学杂志》1991,42(10):2727-2737
Interaction in the system isotactic polypropylene–calcite was investigated using X-ray diffraction and transmission electron microscopy. Calcite acts as a weak nucleation agent for polypropylene crystallization and its activity could be increased or decreased by a suitable surface treatment. Investigation of the morphology on the polypropylene–calcite interface using calcite single crystals disclosed the tendency of polypropylene for epitaxial crystallization along preferred substrate crystallographic directions. This tendency was analogous to polymer crystallization on other ionic crystals. 相似文献
13.
通过在抗冲聚丙烯基础树脂中添加自主研制的酰胺型高效β成核剂FB-1,在提高聚丙烯耐热温度的同时有效提高聚丙烯的冲击强度,介绍β成核剂的复配及超细化,研究β成核剂含量对共聚聚丙烯EPS30R冲击强度的影响,考察β成核剂改性聚丙烯的加工稳定性及β成核剂改性共聚聚丙烯的结晶行为。结果表明,加入成核剂后,聚丙烯冲击性能显著提高,β晶型聚丙烯的热稳定性及反复加工性能良好, FB-1成核剂能有效促进聚丙烯中β晶型的形成,而且β成核剂只改变β晶型含量,不改变其微观结构,β成核剂对聚丙烯中的α晶型没有影响。 相似文献
14.
研究了磁化处理对溶液在聚丙烯填料表面润湿性能的影响。研究结果表明 ,经磁化处理后 ,溶液在聚丙烯填料表面的接触角随着磁感应强度的增强而下降 ,即磁化处理能够改变溶液在聚丙烯填料表面的润湿性能。定量计算表明 ,磁化处理后 ,醇类水溶液在聚丙烯填料表面的润湿性能可提高 2 0 %以上。通过对实验数据的回归 ,得出了接触角θ的关联式 ,该研究结果对聚丙烯填料的工程应用具有参考价值 相似文献
15.
Viera Khunova M. M. Sain Zdena Brunovska 《Polymer-Plastics Technology and Engineering》2013,52(4):311-320
The effect of incorporation of maleic anhydride grafted polypropylene on the properties of composites based on separately filled polypropylene and ethylene–propylene copolymer was studied. The tensile strength and impact resistance of talc-filled polypropylene composite can be improved by optimizing the additive concentrations. On the other hand, the impact resistance of talc-filled ethylene–propylene copolymer composite hardly shows any positive effect due to the addition of maleic anhydride grafted polypropylene. The determination of melt flow index for both composite systems studied, however, indicates that addition of maleic anhydride grafted polypropylene lowers the melt viscosity of highly loaded composites. 相似文献
16.
The effects of the molecular weight of polypropylene, nucleating agent, and types of stabilizers on the grafting of methylmethacrylate onto polypropylene sheets were examined. The oxidation of polypropylene sheet surfaces exposed to air after irradiation was studied by measuring survey scan spectra with an X-ray photoelectron spectrometer (XPS). The 1,1-diphenyl-2-picrylhydrazyl (DPPH) technique was utilized to evaluate the concentration of peroxide formed on the irradiated polypropylene sheet by counting the quantity of DPPH consumed by the reaction of peroxide radicals with DPPH. Plastics stabilizers caused a decrease in the concentration of peroxide in the polymer as well as trapped radicals. It was shown that the stabilizer in polypropylene markedly decreased the grafting of methylmethacrylate onto polypropylene. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 2323–2330, 1998 相似文献
17.
18.
The melt fracture behaviors of linear and branched polypropylene resins with foaming additives were investigated. The effects of branching, processing temperature, additives, and blowing agent on the surface melt fracture of polypropylene materials were thoroughly studied. A CCD camera was installed at the die exit to precisely observe the onset of surface melt fracture of extruded foams. The critical wall shear stress was determined for various linear and branched polypropylene resins using a capillary die. It was found that the branching required to foam polypropylene resins also promotes melt fracture: the critical shear stress was decreased by 0.0175 MPa with an increase of 0.1 n/1000c in long‐chain branching. It was also observed that the dissolved blowing agent (butane) significantly suppressed the melt fracture of both linear and branched polypropylene resins. On the other hand, a noticeable increase in the critical shear stress of branched polypropylene materials was observed with the nucleating agent (talc) and the aging modifier (glycerol mono stearate), whereas almost negligible effect of the additives on the critical shear stress was observed for linear polypropylene materials. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
19.
20.
抗氧剂与分子量调节剂在聚丙烯中相互作用的研究 总被引:4,自引:0,他引:4
研究了抗氧剂、分子量调节剂对聚丙烯的作用。实验表明在抗氧剂/分子量调节剂(重量比)为5~15的范围内,有稳态流动区间出现;采用预先加入分子量调节剂然后加入抗氧剂的方式,既可调节聚丙烯流动性,又可达到防止氧化的目的。 相似文献