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2022 1

2014 2

2008 2

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PP 2

HDPE 1

WPC 1

复合材料 1

性能研究 1

物理合金化 1

结晶动力学 1

聚丙烯 1

聚乙烯 1

蜂窝结构 1

非等温结晶 1

麦秸粉 1

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麦秸粉与HDPE/PP基复合材料的制备及性能研究

杨兆哲,许民

《中国工程科学》 2014年第16卷第4期页码 30-33

摘要：

本文采用麦秸粉为增强体，分别与高密度聚乙烯（HDPE）、聚丙烯（PP）热塑性塑料基体采用挤出方式混合制备木塑复合材料，研究麦秸粉与HDPE、PP的配比对复合材料性能的影响。加入少量麦秸粉使木塑复合材料力学性能降低，随着麦秸粉含量的增加，复合材料的力学性能呈提高的趋势；当麦秸粉含量超过一定比例时，木塑复合材料力学性能降低，且冲击性能降低明显；本次试验HDPE基木塑复合材料力学强度略高于PP

关键词：麦秸粉 HDPE PP 复合材料性能研究

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Synthesis and characterization of macromolecular surface modifier PP--PEG for polypropylene

CHEN Hanjia, SHI Xuhua, ZHU Yafei, ZHANG Yi, XU Jiarui

《化学科学与工程前沿（英文）》 2008年第2卷第1期页码 102-108 doi: 10.1007/s11705-008-0018-z

摘要： A novel macromolecular surface modifier, polypropylene-grafted-poly(ethylene glycol) copolymer (PP--PEG), was synthesized by coupling polypropylene containing maleic anhydride with monohydroxyl-terminated poly(ethylene glycol). The effects of the reaction condition on the graft reactions were studied. The copolymers were characterized by IR, H NMR, thermogravimetry (TG) and differential scanning calorimetry (DSC). The results indicated that the graft reactions were hindered by increasing the molecular weight of PP or PEG. The graft copolymer was found to have a higher initial thermal degradation temperature and lower crystallization capacity as compared with pure PP, and the side chain of PEG hindered the PP chain from forming a perfect ? crystal. The thermal stability of PP--PEG decreased with the increasing content or molecular weight of PEG. The copolymers were blended with polypropylene to modify the surface hydrophilicity of the products. The results of attenuated total reflectance FTIR spectroscopy (ATR-FTIR) showed that PP--PEG could diffuse preferably onto the surface of the blends and be suitable as an effectual macromolecular surface modifier for PP.

关键词： polypropylene crystallization capacity attenuated hydrophilicity reflectance

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木粉/聚丙烯复合材料的非等温结晶动力学分析

黄浪,王海刚,王清文

《中国工程科学》 2014年第16卷第4期页码 21-24

摘要：

通过共混造粒热压方法制备聚丙烯（PP）基木塑复合材料（WPC），用差示扫描量热法研究其非等温结晶行为，分别用Jeziorny 法和Mo法对所得的数据进行处理分析结果表明：Jeziorny 法和Mo法能较理想地处理PP 基WPC的非等温结晶过程，复合材料中木粉的加入缩短了结晶时间，提高了PP 的结晶温度，降低了结晶速率。

关键词： PP WPC 非等温结晶结晶动力学

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Investigation on multiple-melting behavior of nano-CaCO3/polypropylene composites

LIN Zhidan, ZENG Chunlian, MAI Kancheng

《化学科学与工程前沿（英文）》 2007年第1卷第1期页码 81-86 doi: 10.1007/s11705-007-0017-5

摘要： The multiple melting-peak behavior of polypropylene (PP) in nano-CaCO/PP composites and modified nano-CaCO/PP composites were investigated under the condition of isothermal crystallization and nonisothermal crystallization. The result indicated that the addition of nano-CaCO markedly increased the crystallization temperatures of PP and induced the formation of the β-crystal of PP. The crystallization temperatures of nano-CaCO/PP composites modified by reactive monomers were further increased, but the melting-peak intensity of the β-crystal of PP was not greatly influenced. While in the presence of dicumyl peroxide, nano-CaCO/PP composites modified by reactive monomers led to the significant increase in the melting-peak intensity of the β-crystal of PP. The double melting-peak of PP was observed, which was attributed to the formation of two kinds of different crystallization forms of α-crystal or β-crystal during the crystallization of PP. With the increase of crystallization temperatures, the double melting-peak moved toward the high-temperature side. The intensity of high-temperature melting peak was higher than that of low-temperature melting peak in nano-CaCO/PP composites. While in modified nano-CaCO/PP composites crystallized at higher temperature, the intensity of high-temperature melting peak was lower than that of low-temperature melting peak. The isothermal crystallization time had little effect on the melting temperatures.

关键词： polypropylene nano-CaCO/PP presence melting-peak behavior low-temperature

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Preparation and properties of nano SiO2 core-shell structured additives and their nanocomposite with polypropylene

KE Yangchuan, SUN Mingzhuo, SONG Yanxin, YANG GuangFu

《化学科学与工程前沿（英文）》 2007年第1卷第1期页码 76-80 doi: 10.1007/s11705-007-0016-6

摘要： To improve the performance of traditional nucleation additives and their compatibility with other additives, as well as to solve complex problems in practical applications, SiO precursors were reactively grafted in situ with the symmetrical hydroxyl groups of the nucleation agents. With this approach, the dissymmetrical part of the nucleation agents plays an important role. As a result, the prepared composite additive the nanoparticle precursor (NPP0) produces excellent results. The NPP0-PP composite has a transparency of over 93%, haze lower than 15%, and a heat distortion temperature (HDT) of 142?C, which is more than the 110?C of the pure PP matrix. In addition, it maintains over 90% of the mechanical properties with a deformation coefficient less than 1%. This indicates a strong nanoeffect.

关键词： deformation coefficient distortion temperature excellent NPP0-PP traditional nucleation

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Effect of inhibiting tyrosine kinase Src expression on protein phosphatase 2A and tau phosphorylation

LIU Rong, ZENG Ji, ZHOU Xinwen, WANG Jianzhi, PEI Jinjing

《医学前沿（英文）》 2008年第2卷第3期页码 235-238 doi: 10.1007/s11684-008-0044-8

摘要： The aim of this study is to investigate the effect of tyrosine kinase Src on Tyrosine 307(Y307) phosphorylation, protein phosphatase 2A (PP2A) activity, and on tau phosphorylation. Specific Src siRNA was transfected into cultured mouse neuroblastoma N2a cells to inhibit the expression of Src protein, and the phosphorylation levels of PP2A Y307 and tau at different sites, as well as PP2A activity were detected at different time points after siRNA transfection. Twelve hours after siRNA transfection, the protein level of Src was dramatically decreased, with decreased PP2A Y307 phosphorylation. However, the total PP2A protein level was also decreased, together with a decreased PP2A activity. Tau was hyperphosphorylated at the Ser198/199/202 sites. Multiple factors may be involved in the cellular regulation of PP2A activity. Inhibiting Src expression could induce inactivation of PP2A and tau hyperphosphorylation.

关键词： hyperphosphorylation PP2A activity cellular regulation siRNA siRNA transfection

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面向塑料回收的工业级PP/PE物理合金化技术 Article

瞿金平, 黄照夏, 杨智韬, 张桂珍, 殷小春, 冯彦洪, 何和智, 晋刚, 吴婷, 何光建, 曹贤武

《工程（英文）》 2022年第9卷第2期页码 95-100 doi: 10.1016/j.eng.2021.02.021

摘要：

聚丙烯（PP）和聚乙烯（PE）在日常生活中无处不在。但PP和PE的相容性较差，通过简单熔融共混难以制备具有良好力学性能的合金，为废弃PP、PE的回收再利用带来难题。此外，由于可能存在的环境污染问题，传统的添加相容剂诱导增容的方法也难以得到广泛应用。在本文中，受到中国传统榨油方法的启发，我们报道了一种简单的、可工业化的无添加制备高度取向蜂窝结构PP/PE 二元共混物的新技术。

关键词：聚丙烯聚乙烯物理合金化蜂窝结构