新型PP/IPN相变纤维的纺制

以聚乙二醇丙烯酸酯为相容剂,将聚N-羟甲基丙烯酰胺/聚乙二醇互穿网络聚合物(简称IPN)与聚丙烯(PP)共混并纺丝,制备新型PP/IPN相变纤维。测试了共混物的流变性能,共混纤维的力学性能、热性能及回潮率。结果表明:共混物为切力变稀流体,共混纤维断裂强度随IPN含量的增加先增大后下降,相变焓随IPN含量的增大而提高,共混纤维的吸湿能力较纯PP高。当w(IPN)为20%时,断裂强度保持在3 cN/dtex以上,熔融相变焓达17.10 J/g,回潮率达0.68%。     

玄武岩纤维增强PVDF/PP/PETG共混物及性能的研究

通过熔融共混法制备了聚偏氟乙烯/聚丙烯/聚对苯二甲酸乙二醇1,4环己二醇酯（PVDF/PP/PETG）共混物,利用玄武岩纤维对其进行增强改性,并采用扫描电子显微镜、转矩流变仪、维卡软化点测试仪等测试仪器对共混物的形态、黏度、耐热性和力学性能等进行了研究。结果表明,230 ℃时,共混物中PVDF、PP和PETG属两两不相容体系,PVDF和PP呈现连续相结构,而PETG则以球状形态分散在体系中;经玄武岩纤维增强改性后,复合材料的拉伸强度和弯曲强度随着玄武岩纤维含量的增加而增大,且当其含量为30 %（质量分数,下同）时,复合材料的拉伸强度和弯曲强度分别增加到44.0 MPa和67.9 MPa;共混物的维卡软化点从126.7 ℃提高到141.7 ℃。     

PP/COPET/ZnO三元共混物的结构与性能研究

以氧化锌(ZnO)为抗菌剂、水溶性聚酯(COPET)为成孔剂,通过共混纺丝和碱处理,制备了具有多孔结构的、具有吸湿和抗菌功能的聚丙烯(PP)纤维。研究发现,PP/COPET/ZnO三元共混物的密度和结晶度随COPET含量增加而增大;COPET质量分数为9%的共混物的结晶特性略优于3%的;COPET质量分数为6%时纤维的保水率最大;共混纤维对大肠杆菌、枯草杆菌、八叠球菌均有抗菌敏感性。     

降解PP/EPDM共混物的力学性能

用过氧化二异丙苯(DCP)将聚丙烯(PP)降解,制备降解PP与三元乙丙橡胶(EPDM)共混物,测试降解PP/EPDM共混物的冲击和拉伸性能,研究共混物的脆—韧转变,结果发现温度和EPDM含量对PP/EPDM共混物的韧性影响规律是相同的,增加温度和增加EPDM含量都能使PP/EPDM共混物的韧性增加。     

稀土β成核剂对PP/OBC共混体系力学和结晶性能的影响

以均聚聚丙烯(PP)为原料,乙烯-辛烯嵌段共聚物(OBC)为增韧材料,稀土化合物(WBGⅡ)为β成核剂制备了PP/OBC共混体系,分析了WBGⅡ对PP/OBC共混体系结晶性能、晶型和晶体形态的影响,并测试了共混体系的力学性能。结果表明,随着OBC含量的增加,PP/OBC共混体系缺口冲击强度和断裂伸长率明显增大,拉伸强度和弯曲强度随之下降;含1.0%WBGⅡ母粒、15%OBC的PP/OBC共混体系,在152℃附近出现β晶型的特征熔融峰,结晶温度比纯PP提高了10.88℃,β晶型相对含量为21.94%,PP球晶尺寸减小,缺口冲击强度和断裂伸长率分别提高了264.82%和367.66%。     

COP/PP共混物的流变性能

采用 CFT-5 0 0型毛细管流变仪研究了含 COP(含 -SO3N a的共聚酯 ) / PP共混物的流变性能。结果表明 :COP/ PP共混物为假塑性流动 ,其偏离牛顿流动行为的程度与共混物构成有关。在 2 65℃和 2 80℃时 ,COP/ PP共混物的表观粘度随 COP含量的增加而减小 ;COP含量增加 ,共混物的粘温依赖性增大。     

纳米纤维用PP/CAB共混母粒中分散相尺寸的影响因素研究

利用相分离的方法制备热塑性聚丙烯(PP)纳米纤维,将不相容的PP和醋酸丁酸纤维素(CAB)两种聚合物在双螺杆挤出机中共混,制备出合适的母粒用于熔融静电纺丝。通过不同条件下的实验,研究了影响PP分散相粒子尺寸大小的因素,利用扫描电子显微镜观察了共混物的形态,并通过旋转流变仪测量了共混物在不同温度和不同剪切速率下的流变行为。结果表明,PP含量和熔融温度对分散相粒子尺寸的影响最为显著,其次为共混时间,螺杆转速的影响最小;当PP质量分数为20%,熔融温度为210℃,螺杆转速为25 r/min,共混时间为4 min时,可得到尺寸较小的PP分散相粒子。将上述条件下制备的母粒通过熔融静电纺丝技术制备PP/CAB纤维,经丙酮处理除去CAB,得到的PP纳米纤维的平均直径为320 nm左右,与直接熔融静电纺丝制备的PP纤维(平均直径为3.5μm左右)相比,纤维的直径降低了一个数量级,使得纤维细化。     

纳米CaCO_3/EVA/PP共混制备多孔聚丙烯纤维

以纳米CaCO3为成孔剂,与聚丙烯(PP)、乙烯-乙酸乙烯酯嵌段共聚物(EVA)相混合制得共混纤维,将共混纤维进行酸处理和醇解处理后得到多孔聚丙烯纤维。研究了纳米CaCO3/EVA/PP共混物的力学性能,考察了纳米CaCO3/EVA/PP共混纤维的回潮率与表面形态。结果表明:随着EVA含量的增加,纳米CaCO3/EVA/PP共混纤维的力学性能下降,回潮率上升,纤维表面的微孔更加密集、均匀。     

微硅粉改性聚丙烯纤维的制备与性能研究

将微硅粉与聚丙烯(PP)按质量比25∶75进行混合,在190℃温度下熔融挤出造粒,制得母粒,再将母粒按微硅粉质量分数为0~25%与PP配成微硅粉/PP共混物,在共混物中加入质量分数5%马来酸酐接枝PP(PP-g-MA),通过熔融纺丝制备初生纤维,初生纤维经拉伸、热定型制得微硅粉改性PP纤维,研究了微硅粉/PP共混物的流变性能和改性PP纤维的结构与性能。结果表明:微硅粉/PP共混物为非牛顿流体,低含量的微硅粉可以降低PP树脂的黏度,提升PP加工流动性;PP-g-MA的加入增强了微硅粉和PP的相容性,微硅粉质量分数小于20%时,微硅粉能均匀分散到PP中;微硅粉的加入,降低了微硅粉改性PP纤维的接触角,但使其力学性能有所降低;当添加微硅粉质量分数为15%时,微硅粉改性PP纤维的接触角为81.99°,断裂强度为4.60 cN/dtex,断裂伸长率为32.78%。     

芳酰胺类化合物对PP/OBC共混材料性能影响

以均聚聚丙烯(PP)为原料,乙烯-辛烯嵌段共聚物(OBC)为增韧材料,芳酰胺类化合物(TMB-5)为成核剂,采用双螺杆挤出和注塑成型方法制备PP/OBC共混材料,用DSC、WAXD和POM分析了TMB-5对PP/OBC共混材料结晶性能、晶型和晶体形态的影响,并测试了共混材料的力学性能。结果表明:随着OBC含量的增加,PP/OBC共混材料缺口冲击强度和断裂伸长率明显增大,拉伸强度和弯曲强度有所下降;含1.0%TMB-5母粒、15%OBC的PP/OBC共混材料,于152℃附近出现β晶型的特征熔融峰,熔融结晶温度比纯PP提高了11.68℃,β晶型相对含量为52.74%,PP球晶尺寸减小,缺口冲击强度和断裂伸长率分别提高了236.46%和256.01%,柔韧性大幅度提高。     

聚丙烯/分子筛共混纤维的结构与性能

用钛酸酯偶联剂对分子筛进行表面处理,按一定比例与聚丙烯(PP)切片共混纺丝,制得PP/分子筛共混纤维,研究PP/分子筛共混纤维的结构与性能。结果表明:当纤维中分子筛的质量分数为1%时,PP/分子筛共混纺丝纤维的可纺性好,断裂强度比纯PP纤维提高31.85%,上染率提高44.86%,初始模量、断裂功、回潮率均有所提高;与纯PP纤维相比,PP/分子筛共混纤维的结晶度略小、晶粒变大,取向度降低,纤维的染色性、吸湿性得到改善。分子筛与偶联剂发生化学反应,有利于分子筛和PP的结合,适当的分子筛含量时,纤维的力学性能有所提高。     

聚丙烯/聚苯乙烯/膨润土共混纤维研究

研究了聚丙烯(PP)纤维可染改性添加剂聚苯乙烯/膨润土(PS/Garamite)杂化复合粒子的原位悬浮聚合及PP/PS/Garamite共混纤维的熔纺成形。对聚合产物中膨润土的层间距、PP/PS/Garamite共混体系中PP的结晶形态、共混纤维的热性能及染色性能进行了表征。结果表明:聚合过程中膨润土的层间距几乎没有变化,添加剂的加入使共混纤维的熔点降低,结晶温度从115℃升高到117℃,结晶度从44.2%降低至40.2%,无定形区域增加。采用分散染料染色,共混改性纤维具有较好的染色深度。     

PHB/PLLA/PEO共混纤维的晶态结构与拉伸性能研究

采用溶液干纺法制备了聚β-羟基丁酸酯/聚乳酸/聚氧乙烯(PHB/PLLA/PEO)共混纤维,研究了PHB/PLLA/PEO初生纤维的晶态结构、在50℃和110℃下拉伸后共混纤维的力学性能及表面形态。结果表明:PHB与PLLA在PHB/PLLA/PEO共混纤维中的晶型均为α晶型;初生纤维经50℃和110℃拉伸2倍后,纤维的断裂强度均有所增加,断裂伸长率减小,50℃拉伸的纤维断裂强度高于110℃拉伸,其断裂方式均为韧性断裂;w(PEO)为5%,PHB/PLLA质量比为1:1,50℃拉伸2倍的PHB/PLLA/PEO共混纤维断裂强度为0.471 cN/dtex,断裂伸长率为34.05%     

CHARACTERIZATION OF MICROCELLULAR FOAMED POLYOLEFIN BLEND COMPOSITES WITH WOOD FIBER

The effects of wood fiber content on the void fraction, cell morphology, and notched Izod impact strength of microcellular foamed HDPE/PP blend composites with wood fiber were studied. The influence of wood fiber content on the carbon dioxide adsorption and desorption in the samples was also examined. Adsorption of carbon dioxide decreased with increased wood fiber content. Gas diffusion rates were faster as wood fiber content increased. The void fraction decreased dramatically when wood fiber was introduced in the blend. Environmental scanning electron microscopy (ESEM) was used to investigate the effects of wood fiber content on cell morphology. The 30:70 HDPE/PP polymer blend without wood fiber resulted in a high void fraction, with a uniform and well-developed microcellular structure, but when wood fiber was introduced, a uniform and well-developed microcellular structure could not be produced. The effects of foaming on Izod impact strength were dependent on wood fiber content.     

羊毛粉/PP共混纺丝和复合纺丝纤维的研究

采用高压空气粉碎羊毛制得的羊毛粉,与聚丙烯(PP)熔融共混纺丝和皮芯型复合纺丝,分别制得羊毛粉/PP共混纤维和复合纤维。对比分析了羊毛粉/PP共混纤维、复合纤维及纯PP纤维的结构和性能。结果表明:羊毛粉/PP共混纤维的断裂强度、初始模量高于复合纤维及纯PP纤维,其大小顺序依次为共混纤维、纯PP纤维、复合纤维;羊毛粉/PP共混纤维的表面染色深度(K/S值)高于复合纤维及PP纤维,其大小顺序依次为共混纤维、复合纤维、纯PP纤维;羊毛粉/PP共混纤维和复合纤维的回潮率均高于纯PP纤维,其大小顺序依次为复合纤维、共混纤维、纯PP纤维。     

Microcellular foaming of PE/PP blends

Three different polyethylene/polypropylene (PE/PP) blends were microcellular foamed and their crystallinities and melt strengths were investigated. The relationship between crystallinity, melt strength, and cellular structure was studied. Experimental results showed that the three blends had similar variation patterns in respect of crystallinity, melt strength, and cellular structure, and these variation patterns were correlative for each blend. For all blends, the melt strength and PP melting point initially heightened and then lowered, the PP crystallinity first decreased, and then increased as the PE content increased. At PE content of 30%, the melt strength and PP melting point were highest and the PP crystallinity was least. The blend with lower PP crystallinity and higher melt strength had better cellular structure and broader microcellular foaming temperature range. So, three blends had best cellular structure at PE content of 30%. Furthermore, when compared with PE/homopolymer (hPP) blend, the PE/copolymer PP (cPP) blend had higher melt strength, better cellular structure, and wider microcellular foaming temperature range, so it was more suited to be microcellular foamed. Whereas LDPE/cPP blend had the broadest microcellular foaming temperature range because of its highest melt strength within three blends. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 4149–4159, 2007     

Physical modification of polypropylene. III. Novel morphology of polypropylene and poly(ethylene-co-vinyl alcohol) with epoxy blend fibers

In this study, the novel morphology of polypropylene (PP) and poly(ethylene-co-vinyl alcohol) (EVOH) blend fibers is described. More precisely, the blend fibers of PP–EVOH containing a small amount of EVOH (1, 3, 5, 7, and 9% by weight), with and without epoxy (1 wt %), have been melt-spun at a constant spinning velocity (500 m/min). For the as-spun fiber, both the initial modulus and the tenacity increased with the increase in the EVOH content. The blend fibers with three draw ratios (2, 3, and 4) drawn at room temperature. The scanning electron microscopic study showed that a draw ratio of 2 reveals little about the morphological changes, whereas a draw ratio of 4 showed a streak structure perpendicular to the fiber axis for PP–EVOH (91/9 wt %) blend fibers. In addition, epoxy (1 wt %) containing PP–EVOH (91/9 wt %) blend fiber showed latitudinal streaks. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 1049–1057, 1999     

MPP无卤阻燃聚丙烯纤维的辐照改性研究

采用自制季戊四醇螺环磷酸酯双蜜胺盐(MPP)无卤阻燃剂与聚丙烯(PP)进行共混纺丝,制备了无卤阻燃PP纤维,采用低能电子辐照对无卤阻燃PP纤维进行改性,并对MPP的结构、PP纤维的力学性能及阻燃性能进行了表征。结果表明:自制MPP为预期结构;随着MPP含量的增加,PP纤维的极限氧指数(LOI)增大,但其断裂强度有所下降;MPP质量分数为8%时,纤维断裂强度为6.02 cN/dtex,LOI为24.5%;随低能电子辐照量的增大,MPP质量分数8%的阻燃PP纤维的LOI大幅度增加;当电子辐照量为200 kGy时,阻燃PP纤维的LOI为33.8%,断裂强度为3.08 cN/dtex,起始分解温度和残炭率比纯PP纤维均有较大幅度增加,燃烧形成连续致密的炭层。     

PP/共聚酯共混纤维染色热力学研究

采用聚丙烯(PP)与常压阳离子染料可染共聚酯共混纺丝,共混纤维在不同温度(100,117℃)和不 同的阳离子蓝X-GRRL染料浓度中染色至饱和,研究了共混纤维各种染色热力学参数。共混纤维在该染料 染浴中100℃时的染色标准亲和力为-7.94 kJ／mol,100～117℃的染色热为4.21kJ／mol,100℃时的染色熵 为-10.0J／(mol·K)。     

PP／EVA／COPET共混纤维醇碱处理研究

将聚丙烯（PP）、乙烯-醋酸乙烯酯共聚物（EVA）和可溶性共聚酯（COPET）按一定比例共混制得PP／EVA／COPET共混纤维。采用正交实验法研究了醇碱处理备件及共混纤维组成对减量率的影响,考察了处理前后纤维的结构。结果表明,处理温度时减量率的影响较大。在浴比为1：40、季铵盐浓度为1g·L-1的条件下,最佳醇解处理工艺条件为：碱浓度20g·L-1、时间40min、温度55℃;纤维的减量率可达到1．471％。达到碱水解平衡时,纤维表面产生微孔和沟槽.