热致型液晶聚合物的玻璃态结构及形成热力学和动力学

利用热台偏光显微镜、差示扫描量热法(DSC)、广角X-射线衍射(WAXD)等分析测试手段,对聚1,4-苯二氧乙酸-1,8-二氧代辛撑基二苯酚酯的织态结构及相态进行了研究。结果表明,该聚合物在经过一次加热冷却循环后。生成了液晶玻璃态。对相转变的转变熵值的分析表明,上述结论是正确的。并在热力学与动力学共同作用的基础上,讨论了热致型液晶聚合物液晶玻璃态的形成,提出了固化温度大于结晶温度是液晶玻璃态产生的必要条件。     

高收缩涤纶长丝性能研究

本文以高速纺卷烧丝POY为原料，经过调节不同的牵伸速度和温度等参数制备了具有10－60％收缩性能的涤纶长丝，测试了高收缩涤纶长丝收缩前后的结晶度和取向度的变化，讨论了收缩温度和时间对纤维收缩的影响，以及高收缩纤维的收缩率和纤维强伸度的关系。     

低档兔毛纺纱工艺路线探索

低档兔毛纤维短,本文采用棉型纺纱系统,可以纺制18 tex以细的纱,这样有利于开发薄型产品。但纯兔毛纱强力较小,可用涤丝包芯方式采加固。产品经济实惠,适合内销市场需要。本文工艺采用短流程,基本上在棉纺设备上加以改装后纺制成纱。     

松香改性不饱和聚酯反应动力学研究

本研究测定了顺丁烯二酸酐、邻苯二甲酸酐和乙二醇缩聚反应以及顺丁烯二酸酐与松香Ｄｉｅｌｓ—Ａｌｄｅｒ加成反应的动力学参数，确定它们的反应级数均为二级．求出不同温度下的反应速度常数及宏观活化能．为合成性能优良的松香改性不饱和聚酯树脂提供了最佳工艺条件．     

竹涤包芯纱线产品工艺研究及质量分析

阐述了用新一代“绿色纤维”———竹浆纤维作外包纤维,涤纶FDY长丝作芯丝生产的机织用包芯纱和针织用股线的设计思路、产品风格.并对生产竹涤包芯纱线过程中主要技术难点、工艺参数的选配以及采取的技术措施进行了分析.     

多检测凝胶渗透色谱技术在超支化聚氨酯表征中的应用

采用凝胶渗透色谱(GPC)／示差折光指数(RI)／直角激光光散射(RALLS)／示差粘度(DV)三检测联用技术在25℃的四氢呋喃(THF)中对超支化聚氨酯及与其结构类似的线性聚氨酯进行了表征．比较了超支化聚合物和线性聚合物lg[η]，lgRg与lgMr的关系，计算了超支化聚氨酯的结构因子ε．结果表明，超支化聚合物具有较低的特性粘数([η])，较小的旋转半径(Rg)；超支化聚氨酯不符合普适标定规律．     

邻苯二甲酸二元醇聚酯合成、表征与热解动力学

以钛酸四正丁酯为催化剂,2-乙基己醇为封端剂合成邻苯二甲酸聚1,2-丙二醇酯、邻苯二甲酸聚1,3-丁二醇酯和邻苯二甲酸聚1,4-丁二醇酯系列聚酯.经化学方法分析比较3种样品的酸值、羟值和皂化值.通过红外光谱仪、凝胶渗透色谱和热重分析仪-差示量热扫描仪等仪器分别分析比较了3种聚酯样品的分子结构、数均相对分子质量和分布以及热稳定性能,理论计算了热分解表观活化能.邻苯二甲酸聚1,2-丙二醇酯、邻苯二甲酸聚1,3-丁二醇酯和邻苯二甲酸聚1,4-丁二醇的分解焓分别为648.7 J/g、822.6 J/g和266.7 J/g,热分解表观活化能分别为77.36 kJ/mol、66.80 kJ/mol和71.22 kJ/mol.     

超支化聚酯Boltorn H20的改性研究

超支化聚酯Boltorn H20分子末端含有很多羟基,采用回流冷凝法,用顺丁烯二酸酐将H20部分端羟基进行改性,从而在H20分子上引入了端羧基.主要讨论了溶剂和改性不同端羟基数目对反应的影响,反应终点采用红外光谱来确定.核磁共振谱图证实了Boltorn H20被成功改性,这为进一步研究超支化聚酯在水性涂料中的应用奠定了基础.     

Physical Characteristics of Knitted Polyester Vascular Prostheses： Can the Wall Be Considered as a Scaffold for Tissue Regeneration？

Recent developments in endovascular surgery (EVAR) have opened new avenues to successfully treat aneurysms with percutaneous deployment of stent-grafts.Manufacturers have preferred to use woven fabrics or micro-porous tubes which are supported by metallic frames or stents.Woven fabrics are much thinner than knits and this permits the use of a smaller delivery catheter.However,since woven constructions are stiffer and have little porosity,the tissue ingrowth is poor or absent.On the other hand,knitted constructions can be considered as a scaffold for tissue ingrowth,and hence they represent an attractive alternative because of their open structure and better conformability in the case of balloon deployment.The present study was undertaken to analyze the properties of two knitted and crimped polyester arterial prototype prostheses,one with and the other without a gelatin coating as sealant.Two commercial controls were also included in the study,namely the uncoated knitted polyester vascular prosthesis VP1200K,and its sealed version,the gelatin coated polyester knitted Gelsoft device,manufactured by Vascutek Ltd.,Scotland,UK.In vitro testing consisted of analyzing the geometry and morphology of the yarn and fabric structures,and measuring the physical and mechanical properties of the grafts,including the water permeability,the longitudinal and radial compliance,and the suture retention strength.In order to compare the different properties of the four samples,tests were also performed on the gelatin coated or sealed devices before and after gelatin removal.The results provided a useful comparison between the prototypes and the commercial control devices.The latter used ten times the amount of gelatin which had been applied as a coating in order to achieve the same low level of impermeability to water.The different amounts of gelatin also explained the different mechanical performance,such as compliance,for these prototype and control prostheses.     

聚对苯二甲酸乙二醇酯生产中终缩聚反应过程模型及其工业应用

从过程机理出发，建立了文题所述模型，在模型仿真的基础，对终缩聚过程的操作变量和产品质量指标的关系进行了详细讨论，结果对实际生产过程具有良好的指导意义。