聚乳酸/二氧化硅静电纺丝复合纤维膜的制备与表征

为提高聚乳酸（PLA）静电纺丝纤维膜的热性能及机械性能,以PLA为基体,正硅酸乙酯为SiO₂前驱体,通过溶胶-凝胶法和静电纺丝工艺制备PLA/SiO₂复合纤维膜。研究表明：通过静电纺丝,SiO₂被成功引入PLA基体制备成纤维膜,其中PLA呈非晶态,且SiO₂增大了PLA的分子间距;SiO₂的引入可以显著提高800 ℃时的残余量;SiO₂可以提高复合纤维膜的断裂强度和断裂伸长率,且当（SiO₂）为1 %时,断裂强度和断裂伸长率分别提高至2.82 MPa和42.2 %;静电纺丝纤维膜内的纤维无序排列,粗细不均匀,SiO₂引入后,PLA的孔洞更加明显、致密。总之,SiO₂引入PLA基体后,复合纤维膜在800 ℃的残余率显著提高,断裂强度及断裂伸长率改善,且形成致密的孔洞结构。     

Fabrication of continuous fiber-reinforced thermoplastic composites with structural gradient from sheath-core type bicomponent fibers

Sheath-core type bicomponent fibers of polypropylene (PP) as a sheath component and thermotropic liquid crystalline polymer (TLCP) as a core component were prepared by the highspeed melt spinning process. Continuous fiber reinforced thermoplastic composites, in which TLCP acts as a reinforcing fiber and PP as a matrix polymer, were fabricated by the compression molding of these fibers. In the melt spinning, the attainable highest take-up velocity of TLCP was improved by co-processing with PP. Tensile modulus and strength of the TLCP component in the PP/TLCP bicomponent fibers increased with an increase in the take-up velocity. Comparison of wide-angle X-ray diffraction patterns of starting bicomponent fibers and fabricated composites indicated that the orientation relaxation of TLCP did not occur in the compression molding process. Accordingly, the tensile modulus and strength of the PP/TLCP composites were similar to those of the bicomponent fibers. Continuous fiber reinforced thermoplastic composites with various types of fiber content distributions were fabricated from the bicomponent fibers in which sheath-core composition was changed gradually in the spinning process. In the three-point bending test, the composites with two different types of symmetric structural gradients, one with higher TLCP fiber content near the surfaces than in the center and the other with higher TLCP content in the center than near the surfaces, exhibited different flexural moduli even though the overall TLCP contents were comparable. In the three-point bending test of a composite with asymmetric structural gradient, the yielding behavior and maximum flexural load varied depending on the direction of load application although the initial flexural moduli were similar.     

全毛针织绒线绞纱防毡缩及其染色工艺

论述了全毛针织绒线绞纱氯化一树脂防缩法．用二氯异氰脲酸盐作为释氯剂，阳离子自交联非硅聚合物为树脂，通过释氯剂的不同用量及处理浴的ｐＨ值和温度变化，研究全毛针织绒线的处理效果．得出采用３％释氯剂滴加（处理浴ｐＨ值为４．５、温度为３０℃）和３％树脂进行绞纱防缩处理，防缩效果达到了国际羊毛局机可洗的标准．选用适当的染料（兰纳素和兰纳洒脱染料），试验释氯剂对色变的影响；对不同的颜色，根据释氯剂对其影响程度的大小，采用不同的处理顺序（先氯化处理后染色或先染色后氯化处理）．对先氯化处理的全毛针织绒线染色性能的研究结果表明，适当地提高染浴的ｐＨ值，降低染浴的始染温度，必要附加入适当的释酸剂控制染浴的ｐＨ值，有利于染色的均匀．防缩后的全毛针织绒线的色牢度符合国际羊毛局机可洗的色牢度要求．     

固体高分辨~(13)C NMR研究γ线辐照对结晶聚乙稀聚集态结构的影响

结晶聚乙烯(PE)经~(60)Coγ线辐照后,用固体高分辨~(13)C NMR CP/DD/MAS方法观测解析了辐射效果与具有片晶结构的结晶相,结晶—橡胶状无定形界面相以及橡胶状无定形相的聚集态结构的关系。考察了各相中的~(13)C核自旋—晶格弛豫和自旋-自旋弛豫行为及辐照对其影响。得到辐照后产生交联,破坏,相转变及晶型变化等有意义的结果,对PE的辐照效应和机制的探讨提供了核磁共振的新实验证据。     

转杯纺半自动接头质量提高的研究

通过对转杯纺半自动接头原理和关键技术的阐述，分析其接头质量不理想的原因，进而提出了3种改进措施，包括采用退捻生成纱尾、改变喂给速度和排除损伤纤维。并通过试验验证了前面两者具有较好的效果，特别是改变喂给速度的方法效果更佳。     

31P CP/MAS NMR of polycrystalline and immobilized phosphines and catalysts with fast sample spinning

Cross‐polarization (CP) at fast magic angle spinning (MAS) frequencies leads to a splitting of the Hartmann–Hahn (HH) matching profile into a centerband and additional bands of higher orders. The matching profiles differ with the substance categories. Therefore, signal intensity is usually lost, when e.g. the routine standard NH₄H₂PO₄ is used for optimizing the ¹H–³¹P HH match prior to measuring phosphines and their metal complexes in polycrystalline or immobilized form. Here, a variety of model compounds, such as Ph₂PCH₂CH₂PPh₂ and (CO)₂Ni(PPh₃)₂, which can be used as ³¹P CP standards for analogous substances or materials are presented. Investigating the influences of MAS frequency, contact time, ¹H pulse power and sample volume on the matching profiles of the model compounds leads to general trends. Thereby, a new strategy for measuring difficult samples with CP at high MAS rates has been developed: their optimum CP parameters are derived from the most intense maxima in the HH matching profiles of the corresponding model compounds. This new strategy is compared with variations of a conventional ramp sequence. Although the latter generally provide smaller signal half‐widths, the new strategy leads to higher signal intensities. The new method was successfully applied to polycrystalline and immobilized phosphines and catalysts. Copyright © 2003 John Wiley & Sons, Ltd.     

细纤维低号纱粘涤织物的染整工艺研究

探讨细粘胶纤维和细涤纶纤维低号纱混纺织物连续化生产的可行性．运用松式、低张力和短流程的连续式印染加工方法，生产出了具有防缩免烫和仿丝绸效果的高档粘涤织物，总结出了一套较为成功的细纤维低号纱粘涤织物染整工艺．     

刷镀Ni－SiC－WC－MoS_2复合镀层钢领的纺纱性能

探索钢领表面处理新技术．选用复合刷镀技术处理钢领内跑道表面，研究复合刷镀钢领的纺纱性能．结果表明，复合刷镀Ｎｉ－ＳｉＣ－ＷＣ－ＭｏＳ２处理后的钢领具有较优的纺纱性能．     

热处理对Tencel纱线强伸性能的影响

纱线的强伸性能极大地影响着它的加工性能和产品的穿着性能，这里测试分析了Tencel、粘胶纱线经不同条件的热处理后其断裂伸长率、断裂强度、弹性模量、断裂比功的变化，通过测试发现不同条件热处理后Tencel纱线的各强伸性能指标均比粘胶纱线的高。