循环利用变型二浴法铬鞣废液的研究

本文对变型二浴法铬鞣废液的循环利用进行了研究。结果表明，变型二浴法铬鞣废液可以进行封闭式循环利用。     

Electrospinning and rheological behavior of poly (vinyl alcohol)/collagen blended solutions

Poly(vinyl alcohol)/collagen (PVA/COL) micro-nanofibers were successfully prepared by electrospinning process. Water, green, and non-toxic was used as the solvent. The electrospun mats consisted of micro-nanoscale fibers with mean diameter ranging from approximately 363 nm to 179 nm. It was observed that the mean diameters of PVA/COL electrospun fibers decreased with increasing collagen content. The effects of PVA/COL blending ratio on the rheological behavior of PVA/COL blended solutions were investigated by rotate rheometer. It was found that PVA/COL blended solutions behaved as Non-Newtonian fluids. With increasing collagen content, the Non-Newtonian index (n) of PVA/COL blended solutions decreased. Meanwhile, a linear relationship was found between the Non-Newtonian index (n) and the mean diameters of the PVA/COL micronanofibers. The chemical structures of PVA/COL electrospun fibers were also characterized by FTIR.     

Compatibility and Properties of Biodegradable Blend Films with Gelatin and Poly（vinyl alcohol）

The blend films with gelatin and poly（vinyl alcohol） （PVA） were prepared by a solution casting method. The compatibility between gelatin and PVA in the blend films was investigated. The transmittance, Fourier-transform infrared spectroscopy （FTIR）, x-ray diffraction （XRD）, thermogravimetry analysis （TG）, and differential scanning calorimetry （DSC） were employed to characterize the resultant blend films. According to optic result, the opacity of the blend film at the ratio of 20/80 （w/w, Gel to PVA） was the lowest, indicating the best compatibility between Gel and PVA at the ratio. The results oflR, XRD, DSC, and TG revealed an intensive interaction and good compatibility between them in the blend film at the ratio. The mechanical properties and solubility showed that PVA content in the blend films obviously affected the elongation at break and solubility. The mechanical properties and water resistance of gelatin film may be improved by the introduetion of PVA.     

铬的污染源及其危害

本文介绍了铬污染的来源并对其危害进行了分析和讨论，从而说明了治理铬污染的必要性和重要性。     

汗液对皮革耐热稳定性的影响

采用热台显微镜、热重分析等方法研究了未鞣制皮粉、铬鞣皮粉和戊二醛鞣制皮粉的热收缩和热降解行为，探索了这些试样在受到汗液浸泡作用时热收缩和热降解行为方面所发生的变化，讨论了发生这些变化的机理。     

正丁胺为扩链剂合成水性聚氨酯皮革涂饰剂

采用异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)、聚四氢呋喃(PTMG)为原料制备聚氨酯预聚体,分别以乙二醇(EG)、乙二胺(EN)和正丁胺(n-butylamine)为扩链剂制备了水性聚氨酯皮革涂饰剂,研究了该涂饰剂所成膜的力学性能、断裂伸长率和吸水性。结果表明,以正丁胺为扩链剂制备的水性聚氨酯膜的断裂伸长率最好,高达1454%;其玻璃化转变温度可达-82℃,耐水性也比用其它两种扩链剂合成的产品好。     

影响胶原结构与性能的因素研究进展

胶原及胶原基材料广泛应用于生物医用、皮革、食品、日用化学工业等领域。在加工、应用及保存的过程中,胶原常会受到光照、温度及湿度变化、pH值变化、盐溶液浸泡以及细菌和霉菌侵蚀等作用,使材料的结构发生改变,导致性能变化。本文综述了引起胶原结构与性能变化的主要因素,阐述了紫外光照射、酸与碱溶液、盐溶液与有机溶剂及热作用下,胶原的热稳定性能、三股螺旋链结构及聚集态结构的变化。     

胶原蛋白酶解产物功能特性研究

本文研究了胶原蛋白经酶水解后所得胶原水解物的功能特性。酶解后胶原蛋白分子量减小，胶原酶解产物的吸水性、保水性、溶解性较酶解前都得到提高，但是吸油性、起泡性和泡沫稳定性都明显下降。对胶原蛋白进行有限水解，使其功能特性发生改变，有利于其在化妆品以及食品添加剂等方面的应用。     

鞣制时蒙囿铬液中铬配合物组成的变化和不同铬配合物与胶原的亲合力(续)

2、乙酸盐蒙囿铬液用2.0mol乙酸/molCr铬液于各种pH下鞣制皮粉。乙酸蒙囿铬液由组分Ⅱ、Ⅳ和Ⅴ所组成。图3示出了鞣制时铬配合物组成的变化。pH3.0和4.0时变化很小,pH5.0时变化显著。pH5.0时,组分Ⅳ和Ⅴ的减少分别为轻微和明显,而组分Ⅱ几乎不减少。