防紫外毛涤混纺织物的开发及其性能研究

采用原料创新将抗紫外线涤纶纤维与防缩羊毛混纺,选用不同的混纺比,设计纺纱工艺流程及主要技术参数,选用相同的纱支、不同的经纬密度及织物组织上机织造,得到了不同规格的轻薄面料.测试和分析了不同规格抗紫外线毛涤织物的紫外线防护效果,并对各类织物的热湿舒适性能进行了测试与评价.结果证明,所设计并试织的系列织物具有较好的防紫外线性能和热湿舒适性能;在保证紫外线防护系数符合要求的情况下,织物的紧度不宜过大,以使夏季织物具有较好的热湿舒适性能.     

甜高粱秸秆酒的后期处理及勾兑

甜高粱秸杆含有大约15%～25%的糖分,能发酵产生酒精。通过勾兑可以将原酒制成清香型白酒。勾兑试验结果表明：先用0.1%的活性炭颗粒处理秸秆酒两天,会显著降低酒中的甲醇和杂醇含量;然后再用浓度为3%的活性炭颗粒处理秸秆酒若干天会有效除去酒中的秸秆味;最后,通过勾兑和调味配制出风味独特、酒体完整、具有特殊秸秆香味的清香型甜高粱秸秆白酒。     

Using modulated‐temperature differential scanning calorimetry to study interphases in blends of styrene–butadiene and polybutadiene rubbers filled with a silanized silica nanofiller

Polybutadiene and styrene–butadiene rubber compounds containing a high loading of a precipitated silica nanofiller were prepared. The silica surfaces were pretreated with bis(3‐triethoxysilylpropyl) tetrasulfide to prevent the silica from interfering with the reaction mechanism of sulfur cure in the rubber. The rubber compounds were mixed together for different times and at different temperatures to produce styrene–butadiene rubber/polybutadiene rubber blends. The mass fraction and composition of the interphase in the blends were subsequently determined with modulated‐temperature differential scanning calorimetry. At 60–65°C, the mass fraction of the interphase in the blend increased after the rubbers were mixed together for 10 min, and then it decreased significantly when the mixing time was increased to 20 min. When the two rubbers were mixed together for 7 min at 60–105°C, the mass fraction of the interphase in the blend increased slightly because of a higher mixing temperature. The composition of the interphase in the blend also changed with the mixing time and mixing temperature. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Chemical modification of polyethersulfone nanofiltration membranes: A review

Polysulfone (PS) and poly(ether)sulfone (PES) are often used for synthesis of nanofiltration membranes, due to their chemical, thermal, and mechanical stability. The disadvantage for applying PS/PES is their high hydrophobicity, which increases membrane fouling. To optimize the performance of PS/PES nanofiltration membranes, membranes can be modified. An increase in membrane hydrophilicity is a good method to improve membrane performance. This article reviews chemical (and physicochemical) modification methods applied to increase the hydrophilicity of PS/PES nanofiltration membranes. Modification of poly(ether)sulfone membranes in view of increasing hydrophilicity can be carried out in several ways. Physical or chemical membrane modification processes after formation of the membrane create more hydrophilic surfaces. Such modification processes are (1) graft polymerization that chemically attaches hydrophilic monomers to the membrane surface; (2) plasma treatment, that introduces different functional groups to the membrane surface; and (3) physical preadsorption of hydrophilic components to the membrane surface. Surfactant modification, self‐assembly of hydrophilic nanoparticles and membrane nitrification are also such membrane modification processes. Another approach is based on modification of polymers before membrane formation. This bulk modification implies the modification of membrane materials before membrane synthesis of the incorporation of hydrophilic additives in the membrane matrix during membrane synthesis. Sulfonation, carboxylation, and nitration are such techniques. To conclude, polymer blending also results in membranes with improved surface characteristics. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Crystallization behavior of “wet brush” and “dry brush” blends of PS‐b‐PEO‐b‐PS/h‐PEO

The crystallization behavior of the blending system consists of homopolymer poly(ethylene oxide) (h‐PEO) with different molecular weights, and polystyrene‐block‐poly (ethylene oxide)‐block‐polystyrene (PS‐b‐PEO‐b‐PS) triblock copolymer has been investigated by DSC measurements. The crystallization of PEO block (b‐PEO) in block copolymer occurs under much lower temperature than that of the h‐PEO in the bulk (ΔT > 65 °C), which is attributed to the homogeneous nucleation crystallization behavior of the b‐PEO microdomains. In both the “dry‐brush” and the “wet brush” blending systems, the homogeneous nucleation crystallization temperature of PS‐b‐PEO‐b‐PS/h‐PEO blends increases due to the increase of the domain size. The heterogeneous nucleation crystallization temperatures of h‐PEO in the wet brush blending systems are higher than that of the corresponding h‐PEO in the bulk. At the same time, the heterogeneous nucleation crystallization temperature of b‐PEO10000 decreases from 43°C to 30°C and 40°C in the h‐PEO600 and h‐PEO2000 blending systems, respectively, because of the stretching of the PEO chains in the wet brush. However, this kind of phenomenon does not happen in the dry brush blending systems. The self‐seeding procedure was used to further ascertain the nucleation mechanism in the crystallization process. As a result, the self‐seeding domains have been confirmed, and the difference between the dry brush and wet brush systems has been observed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

冷冻处理对α-PVA/s-PVA共混溶液静电纺丝的影响

将少量的间规聚乙烯醇(s-PVA)加入无规聚乙烯醇(α-PVA)的水溶液中,制得α-PVA/s-PVA共混溶液,对溶液进行冷冻处理,通过高压静电纺丝获得a-PVA/s-PVA纳米纤维毡.研究了s-PVA的加入及冷冻处理对PVA溶液静电纺丝性能的影响.结果表明:随着s-PVA含量的增加,共混溶液的剪切枯度升高,静电纺纤维毡的平均直径减小,拉伸强度增加;冷冻处理后的共混溶液静电纺丝制得的纳米纤维毡与未经冷冻处理的相比,其平均直径增大,珠结减小,拉伸强度提高了约8倍.     

PEEK改性研究进展

简要介绍了PEEK的物理、力学性能及其在机械、石油、化工、医药等领域的应用前景,从纤维增强、无机填料填充、与聚合物共混三个方面对聚醚醚酮的改性技术、聚醚醚酮复合材料的成型工艺及性能进行了讨论.     

PA6／PET切片熔融共混纺丝工艺介绍

在锦纶6（PA6）切片中加入一定数量聚酯（PET）切片进行熔融共混纺丝,主要过程包括配料、熔融、纺丝、侧吹风冷却、上油、拉伸、卷绕成型,获得锦涤FDY工业丝。经测试锦涤工业丝的断裂强度为8．0—8．5cN／dtex,断裂伸长为15％～17％。     

PET/PP共混改性研究

用合成的增容剂SEBS-g-MAH增容PP/PET共混体系,通过改变PET的含量和添加成核剂研究共混体系的力学性能的变化研究结果表明:随着PET含量的逐渐增加,冲击强度逐渐上升、拉伸强度逐渐下降;成核剂的加入对合金的强度有所改善;PET含量在20%～250%时体系的力学性能最佳.     

环氧树脂改性丙烯酸酯共聚物复合乳液的合成及性能研究

通过原位乳液聚合法和物理共混法分别制备了环氧树脂改性丙烯酸酯共聚物复合乳液,并对环氧树脂的用量和不同改性方法进行了研究。通过红外（FT-IR）、透射电镜（TEM）、力学性能测试、耐水性能测试和甲苯溶胀率测试等研究了环氧树脂改性丙烯酸酯共聚物复合乳液及乳胶膜的性能。结果表明,环氧树脂改性后的丙烯酸酯共聚物复合乳液的耐水性能、耐甲苯溶剂性能、力学性能得以提高。当物理共混法的环氧树脂用量为15%,原位乳液聚合法的环氧树脂用量为10%,得到的复合乳液和乳胶膜的综合性能较好。