Alder ene functionalization of polyisobutene oligomer and styrene-butadiene-styrene triblock copolymer

The Alder ene functionalization reaction of double bonds containing macromolecules such as polyisobutene oligomer (PIB) and a styrene-butadiene-styrene triblock copolymer (SBS) samples with maleic anhydride (MAH) or diethyl maleate (DEM) as enophiles is described. The analysis of the products by means of different techniques assesses the addition of the polar molecules to the reactive vinylidene units of the polymer with functional degrees (FD) depending on the type of enophile and polymer reactivity. The role of the reaction conditions and the use as Lewis acids as catalysts are discussed in terms of their influence on the addition reaction extent and on the polymer molecular weight.     

聚异丁烯改性硅橡胶的耐介质性能研究

聚异丁烯（PIB）具有优异的耐介质性能,作为化工添加剂被广泛应用于各种化工材料,将聚异丁烯应用于胶黏剂及密封胶可有效稳定黏度,降低黏温性;同时促进粘接,提高耐介质性能,增加低温下的柔韧性。研究了4种不同的聚异丁烯在单组分室温硫化硅橡胶（RTV-1）中的应用。通过在RTV-1中添加不同相对分子质量的PIB,重点考查PIB对于RTV-1拉伸强度、伸长率及耐介质老化性能的影响。结果发现,添加PIB所制得的RTV-1拉伸强度可达2MPa,伸长率370％左右,同时耐机油、耐水性、耐热氧老化性能优异。     

GPC法研究异丁烯的阳离子聚合反应

用凝胶渗透色谱仪(GPC)来测定阳离子聚合法得到的聚异丁烯,可以验证电子对给予体吡啶对T—BA/TiCl_4/IB/CH_2Cl_2体系的阳离子聚合的影响。     

非稳腔的远场光强分布和光束质量

在对远场光强分布分析的基础上,对非稳腔的光束质量作了详细研究。证明了当遮拦比ε→1时,其远场光强是零阶贝塞尔光束分布。对数值计算结果的物理分析表明:用“桶中功率”曲线是评价非稳腔远场光束质量适用的方法。同时,也指出了这种方法的不足之处。     

像散透镜对超高斯光束的变换特性

利用广义惠更斯菲涅耳衍射积分,并考虑像散的影响,对超高斯光束通过像散透镜后的传输特性作了数值计算和讨论,得出一些新的结论.以桶中功率为参数分析了像散超高斯光束的光束质量,并以数值计算例加以说明.     

乙烯-醋酸乙烯基钢质管道防腐用热熔胶的研究

以EVA树脂为主体树脂制备钢质管道防腐用热熔胶,选用聚合松香为增粘剂,聚异丁烯为增韧剂,研究了不同VA含量、不同熔体指数的EVA树脂、聚合松香及聚异丁烯对热熔胶环球软化点、脆化温度和剥离强度等性能的影响。     

Development of Al-base lubricating grease thickeners

In this paper are presented the results of work on the development of poly-oxo–aluminium acylates that are dissolved in synthetic lubricants, polyalphaolefins (PAOs) andpolyisobutenes (PIBs), and one pharmaceutical mineral oil in order to produce a range of greases that can be food-grade, and have chemical stability. The method of synthesis is described, together with the results using different base oils (two different PAOs, four different polybutenes, and a pharmaceutical grade IS0 VG 46 white mineral oil. These greases are characterised here in terms of their mechanical stability and physical properties. As well as being of food grade, these greases are also shown to be chemically stable.     

Synthesis of well-defined star-branched polymers by stepwise iterative methodology using living anionic polymerization

This article reviews the synthesis of regular and asymmetric star-branched polymers with well-defined structures by methodologies using living anionic polymerization, especially focusing on the synthetic approaches accessible for precisely controlled architectures of star-branched polymers concerning molecular weight, molecular weight distribution, arm number, and composition. The reason for selecting living anionic polymerization from many living/controlled polymerization systems so far developed is that this living polymerization system is still the best to meet the strict requirements for the precise structures of star-branched polymers. Furthermore, we herein mainly introduce a novel and quite versatile stepwise iterative methodology recently developed by our group for the successive synthesis of many-armed and multi-compositional asymmetric star-branched polymers. The methodology basically involves only two sets of the reaction conditions for the entire iterative synthetic sequence. The reaction sequence can be, in principle, limitlessly iterated to introduce a definite number of the same or different polymer segments at each stage of the iteration. As a result, a wide variety of many-armed and multi-compositional asymmetric star-branched polymers can be synthesized.     

对激光光束质量一些问题的认识

从对激光光束质量研究进展开始,讨论了在傍轴和非傍轴范畴内激光光束质量的一些问题,主要是非傍轴光束的光束质量评价。光束传输的非傍轴矢量二阶矩理论可用于计算多种非傍轴光束的M2因子,但对M2因子的物理解释却有困难。例如,在非傍轴范畴,M2因子依赖于束腰宽度与波长之比,并可小于1。但远场发散角之值可趋于90°,这将导致很大的M2因子值。另一方面,若将公式中的光强用时间平均坡印廷矢量z分量代替,桶中功率(PIB),或等价地,?茁 参数可推广用于评价非傍轴光束的远场光束质量。PIB表征了光束功率的可聚焦能力,是一种简明、直观评价不同激光光束的方法。然而,在?茁参数的公式中的束宽是按功率含量百分比定义的,因此双曲线传输规律不再严格成立。     

聚异丁烯在二冲程汽油机油中的应用

论述几种不同分子量、不同来源的聚异丁烯的热氧化性能，并简单说明聚异丁烯在二冲程汽油机油中的应用机理，认为聚异丁烯可以改善二冲程油的润滑性、抗氧化性和排烟性能。