MDI体系聚氨酯弹性体的力学性能研究

考察了多元醇种类、扩链交联剂配比及合成工艺等因素对MDI体系聚氨酯弹性体力学性能的影响。结果表明,使用聚酯类多元醇合成的聚氨酯弹性体力学性能较好;使用半预聚物法合成的聚氨酯弹性体较使用两步法合成的聚氨酯弹性体综合性能优异;扩链交联剂种类及硬段含量对聚氨酯弹性体力学性能起重要作用。     

DETDA扩链剂

<正> 1 简介二乙基甲苯二胺(DETDA)是一种聚氨酯用非MOCA型胺类扩链剂。常温下液态,化学结构(C_2H_5)_2C_6H(H_2N)_2。用于聚氨酯RIM软泡、半硬泡和弹性体等。DETDA扩链的聚氨酯/脲材料,工艺和制品性能多方面优于醇扩链的聚氨酯: ①能提高制品的抗张强度、延伸率和耐热性能; ②DETDA和NCO基团反应时不需采用催化     

丙烯酸改性水性聚氨酯合成方法

介绍了聚氨酯预聚物分散制各水性聚氨酯的方法，讨论了丙烯酸酯改性对水性聚氨酯涂膜的性能影响。分析了亲水性物质、交联剂、扩链剂、引发剂、中和剂、有机溶剂等对水性聚氨酯涂膜外观及性能的影响。     

耐溶剂聚氨酯弹性体性能之研究

采用预聚物法合成耐溶剂聚氨酯弹性体。考察了聚酯多元醇的配比、游离ω(-NCO%)含量变化以及扩链剂并用等因素对耐溶剂聚氨酯性能的影响。结果表明,随着聚酯多元醇76A用量的增加、扩链剂TIPA用量的提高,制品的力学性能和耐溶剂性能提高,TMP(三羟甲基丙烷)能有效降低制品的硬度;预聚物中游离ω(-NCO%)的含量对制品力学性能有重要影响。     

水性聚氨酯原料的选择

详细介绍了制备水性聚氨酯所需的原料，包括聚多元醇(聚酯／聚醚)、二异氰酸酯、亲水扩链剂、交联剂、扩链剂、溶剂、成盐剂及催化剂。并对原料种类、用量多少的选择对制得的水性聚氨酯性能的影响进行了详细的论述。     

影响聚氨酯材料透明性能的相关因素的研究

本文从扩链交联剂、硬段组成、-NCO/-OH比值和固化温度等四个方面讨论了原料和制备条件对聚氨酯材料透明性能的影响。结果表明,扩链交联剂对聚氨酯材料光学性能影响很大;-NCO/-OH比值接近1时,能获得良好的光学透明性;随着硬段物质的增加和固化温度的升高,光学透明性逐渐下降。     

无溶剂喷涂型聚氨酯管道补口涂料的研制

采用多亚甲基多苯基异氰酸酯、聚醚多元醇、扩链剂或交联剂为原料,研制出了A、R双组分无溶剂喷涂型聚氨酯管道补口涂料。讨论了催化剂对凝胶时间的影响,以及A组分中NCO含量、扩链剂或交联剂对涂层性能的影响,同时还对两组分的贮存稳定性进行了研究。结果表明,A组分中NCO含量增加,涂层硬度提高,综合性能也相对提高,但NCO含量过高,柔韧性降低;二乙醇胺和甘油作为扩链剂或交联剂制得的涂层其综合性能高于1,4-丁二醇;所研制的管道补口涂料具有良好的综合性能,能够满足管道补口防腐要求。     

不同硬段结构的液化改性MDI型HTPB-PU弹性体的合成与研究

用端羟基聚丁二烯为原料、液化改性MDI为交联剂、BD或ED为扩链剂合成不同硬段结构的聚丁二烯聚氨酯弹性体，研究了扩链剂种类、用量等对弹性体性能的影响。用扫描电镜研究弹性体应力断裂的断口形态。     

聚氧乙烯苯胺醚在聚氨酯半硬泡制品中的应用

聚氧乙烯苯胺醚是一种优良的聚氨酯半硬泡扩链剂，主要其在聚氨酯半硬泡配方中应用对半硬泡制品性能的影响。     

发泡剂和扩链剂/交联剂对聚酯型聚氨酯泡沫的影响

采用预聚体法制备聚酯型聚氨酯泡沫,利用全水发泡,分别采用1,4-丁二醇(BDO)和三羟甲基丙烷(TMP)做扩链剂和交联剂,考查三者对聚酯型聚氨酯泡沫的性能影响。结果表明:随着水用量的增加,泡沫密度不断下降,力学性能增加,回弹性能呈现先增加后减小的趋势,当水的用量为2. 5～3质量份时泡沫的各项性能最均衡;扩链剂和交联剂的加入使泡沫的力学性能得到提升,同时会降低回弹性能,最佳的扩链剂和交联剂的配比为1. 5质量份的BDO和0. 5质量份的TMP。     

阳离子水性聚氨酯的耐水性研究

通过正交法研究了多元醇、亲水基团含量、交联剂和扩链剂对胶膜吸水率的影响,分别对用丙烯酸酯、环氧树脂和羟基硅油改性的阳离子水性聚氨酯的耐水性进行了研究.实验结果表明,对阳离子水性聚氨酯耐水性影响因素从大到小排列依次是多元醇、亲水基团含量、交联剂和扩链剂.对阳离子水性聚氨酯进行改性能够提高其耐水性.     

改性聚乳酸发泡技术研究进展

综述了近几年国内外改性聚乳酸（PLA）发泡技术的研究进展，针对PLA在发泡方面熔体强度和结晶性能的不足，介绍了通过加入扩链剂、交联剂、成核剂、纤维和其他聚合物等物质来改善PLA发泡性能的方法、效果和机理；最后，对改性聚乳酸发泡技术的未来发展进行了展望。     

Mechanical and swelling properties of HTPB-based copolyurethane networks

Copolyurethanes of hydroxy terminated polybutadiene (HTPB) and ISRO–Polyol (ISPO), an indigenously developed castor-oil based polyol, have been prepared using toluene diiso-cyanate and hexamethylenediisocyanate. The mechanical strength and swelling characteristics of the copolyurethanes cured with trimethylol propane and triethanolamine have been studied to evolve improved solid propellant binders. By varying the ratios of the two hydroxy pre-polymers, chain extenders, and crosslinkers, copolyurethanes having a wide range of tensile strength and elongation could be obtained. Many of these systems are desirable for their use as propellant binders. The results have been explained in terms of the measured crosslink densities and other swelling properties. © 1993 John Wiley & Sons, Inc.     

关于无机填料的颜超微气流粉碎

国产的无机颜料质量和档次与国外存在较大的差距 ,我国在加入世贸组织后 ,其产品会受到一定的冲击。为改进产品质量 ,缩小差距 ,本文综述了气流粉碎技术在制备超微无机颜、填料方面的应用。     

Thermo-rheological analysis of various chain extended recycled poly(ethylene terephthalate)

Three chain extenders, pyromellitic dianhydride (PMDA), ethylene carbonate (EC), and a polymeric-epoxide, were investigated for improving recycled p(ethylene terephthalate) (r-PET) properties with melt extrusion. The amount of additives and processing temperatures were also varied to check for melt degradation. Small amplitude oscillatory shear experiments were performed to probe rheological changes with different chain extenders. Capillary rheometry with haul-off was also performed to measure extensional viscosity and melt strength. Higher loadings of the chain extenders were found to improve properties of r-PET. These chain extenders definitely increased melt viscosities when incorporated at the higher level of the ranges examined, matching that of virgin PET. EC addition resulted in high shear thinning of the polymer. Epoxy and PMDA added to r-PET produced products with the same extensional viscosity as v-PET. Haul-off experiments demonstrate superior performance by epoxy-modified r-PET compared to v-PET.     

扩链剂在氯乙烯聚合中的应用

扩链剂以异氰脲酸三烯丙酯（TAIC）和马来酸双烯丙酯（DAM）及邻苯二甲酸二烯丙酯（DAP）为主要代表,其应用技术要点所涉及的内容有用途、用法、用量、使用成本等。针对这些技术要点问题,以悬浮法和乳液法生产聚氯乙烯树脂为范例作了分析。并对扩链剂在氯乙烯聚合中的应用发展提出了建议。     

扩链剂在阻燃高回弹聚氨酯泡沫中的应用

分别采用三乙醇胺(TEOA)、二乙醇胺(DEOA)和甘油(GLY)三种扩链剂制备阻燃高回弹聚氨酯(FRHRPU)泡沫塑料.探讨了TEOA,DEOA,GLY对FRHRPU泡沫塑料反应活性、泡孔结构及制品力学性能的影响.结果表明:以DEOA为扩链剂制备的FRHRPU泡孔孔径为200.00 μm、氧指数为28.7％,工艺稳定性及力学性能优于其他两种扩链剂制备的FRHRPU.DEOA可广泛应用于FRHRPU泡沫塑料.     

Mechanism for environmental etch of acrylic melamine-based automotive clearcoats: Identification of degradation products

This paper focuses on defining the reaction mechanism involved in the environmental etch of acrylic melamine-based automotive clearcoats via an identification of reaction products. This has been accomplished through a comparative study of products formed on acid treatment of neat crosslinkers, and those formed following laboratory acid treatment and field exposure of acrylic melamine clearcoat systems. Bulk elemental, X-ray photoelectron spectroscopy (XPS), and infrared (IR) analyses of sulfuric acid-treated melamine crosslinkers show that acid hydrolysis results primarily in the formation of melamine sulfate. Melamine sulfate formation was also observed following laboratory and field exposure of acrylic melamine clearcoat systems. These results confirm that the primary mode of melamine crosslink decomposition is through hydrolysis of acetal linkages and subsequent formation of melamine sulfates. However, data show that hydrolysis of pendent amino groups on the triazine ring also occurs. Ford Research Laboratory, P.O. Box 2053, MD 3083 SRL, Dearborn MI 48121. E-mail: pschmit1@ford.com     

耐热氨纶的研究现状

介绍了氨纶的生产现状;对比分析了干法纺丝、熔融纺丝、湿法纺丝和化学反应法的氨纶生产方法;阐述了聚氨酯脲和聚氨酯弹性体耐热性的改进原理和方法;详述了通过聚氨酯软段及硬段、扩链剂、交联剂、添加剂、熔融纺丝等手段改进氨纶耐热性的研究进展;指出使用合适的添加剂和扩链剂或多种改性方法综合运用将是今后提高氨纶的耐热性的主要方向。     

Spun-fiber textured products

The process for spinning fibers from soy isolate is described. Fabrication of so called food analogues and extenders containing spun soy fibers is reviewed. The rationale for the use of fibers in food products and ingredients is explored. Nutritional properties, especially protein quality, of the products are discussed. Emphasis is given to the fact that spun-fiber textured products contain a variety of items, such as soy, wheat, oats, egg albumen, yeast, sodium caseinate, and vegetable oils. The relationship of this variety to applied nutrition is discussed.