复合吸水膨胀橡胶颗粒在二氧化碳中膨胀性能的研究

通过高温高压试验分析了颗粒尺寸、温度、橡胶质量分数对复合吸水膨胀橡胶颗粒在二氧化碳(CO_2)中的膨胀性能。结果表明:在相同温度和压力下,复合吸水膨胀橡胶颗粒尺寸越小和橡胶质量分数越高,其在CO_2中膨胀倍数越大;压力和时间相同时,温度越高,复合吸水膨胀橡胶颗粒在CO_2中膨胀倍数越大。     

掺加橡胶颗粒混凝土材料的性能研究

本文研究橡胶尺寸对橡胶水泥基材料性能的影响,选择三组粒径为6～8mm,3～5mm和0～2mm的橡胶代替骨料制备混凝土,研究制备混凝土材料的稠度和密度、孔径结构、机械强度和干燥收缩性能。结果表明,混凝土材料的稠度和密度随橡胶粒径的增加而降低;对于孔径结构来说,孔体积随着橡胶颗粒粒径尺寸的减小而增加,其中橡胶颗粒粒径尺寸对中孔(50 nm)体积的影响不如橡胶含量因素条件显著;混凝土材料的机械强度随着橡胶颗粒粒径的减小而降低;而混凝土材料干燥收缩率随着橡胶颗粒粒径的减小而增加。     

高光泽耐冲击聚丙烯树脂研究及工业化

利用高低温组合冲击实验机、万能材料试验机、光泽度仪、场发射扫描电子显微镜分析了普通耐冲击聚丙烯树脂的物理性能、光学性能及橡胶相微观结构。结果表明:普通耐冲击聚丙烯橡胶颗粒尺寸主要分布在0.4～1.4μm,光泽度(60°)在35.5%～70.2%。随着耐冲击聚丙烯中橡胶含量的提高及橡胶颗粒尺寸的增大,聚丙烯的光泽度会降低。研究通过调控聚丙烯均聚相及橡胶相的黏度,控制橡胶颗粒尺寸分布于0.1～0.5μm,开发出高光泽耐冲击聚丙烯产品,产品光泽度(60°)达90%,简支梁缺口冲击强度达4.3 kJ/m~2。     

不同粒径的橡胶混凝土低温抗压强度试验研究

通过使用粒径为20目、1 ～3 mm和3～6mm的三种橡胶颗粒制备四种橡胶填充的混凝土.测试混凝土试件在0℃、-10℃、-20℃的低温和常温20℃下的抗压强度,并用电镜扫描低温后橡胶混凝土的微观结构,分析了低温下橡胶混凝土的变化规律.结果 表明:橡胶混凝土的抗压强度在低温环境下得到改善,橡胶颗粒的尺寸对混凝土的抗压强度有影响.直观现象为:橡胶颗粒尺寸越大,温度越低,橡胶混凝土的抗压强度越大.在试验中,当温度为-20℃时,粒径为3～6 mm的橡胶混凝土具有最佳的力学性能.     

相结构调控技术在聚丙烯合金产品开发中应用

利用核磁共振碳谱(13C-NMR)和场发射扫描电子显微镜(FESEM)分析了进口料(7032E3,PF511和SP179)聚丙烯合金的橡胶相组成及微观结构。结果表明:橡胶含量越高,橡胶颗粒尺寸在0.2~1.0μm的比例越高,产品的韧性越好。基于此研究结果,茂名石化开发了新产品聚丙烯合金(K9003,K9017H和K9010),其橡胶相质量分数分别为31.43%,30.48%,30.37%,橡胶颗粒尺寸在0.2~1.0μm的比例分别为77.65%,79.53%,71.25%。新产品弯曲模量、冲击强度接近甚至超越进口料水平。     

朗盛颗粒化橡胶开拓全新市场机遇

德国－勒沃库森．2008年10月13日--全球领先的特殊化学品企业朗盛集团宣布．其位于德国Marl的三元乙丙（EPDM）橡胶颗粒化工厂将于九月下旬正式运营投产。这是公司首次能够以颗粒的形式（颗粒尺寸为2至3毫米）在下属工厂生产并销售该橡胶级别。朗盛已向该工厂投资了数百万欧元．其产能达每小时3至5吨。     

橡胶纳米补强中的逾渗机理和界面相互作用的研究

对不同类型炭黑补强SBR拉伸强度的研究表明,炭黑补强SBR中存在着类似于橡胶增韧塑料的逾渗现象,由此提出橡胶补强临界间距的新概念,并讨论其影响因素.对于炭黑补强SBR体系,存在的一个最大临界粒径(原生粒子直径)为80 nm左右.提出了界面相互作用和最小补强粒子尺寸等橡胶补强设计上的新观点.通过计算机模拟,在分子水平上对橡胶和纳米颗粒间的界面相互作用进行了深入研究,结果表明即使在很强的界面作用(氢键范围)情况下,靠近颗粒表面的分子链仍然具有一定的活动性,在界面处能发生吸附脱附的过程.从热力学和动力学的角度阐述了在颗粒的表面不太可能形成橡胶玻璃化壳层.     

回收的轮胎橡胶碎片可用于制取热塑性塑料混配物

Lehigh技术公司回收的PolyDyne轮胎橡胶粉末可用于制造新型热塑性塑料和热固性塑料混配物，该类混配物可进行大量生产和制造。范围为105-44μm的橡胶小颗粒有很高的表面积，通过改进的聚合物颗粒的相互作用，它们可较容易的组合到聚合物合金中，或橡胶和塑料中。研究结果在2007年10月16～18日美国化学学会橡胶分会第172次技术会议上发布。研究表明，较小颗粒尺寸的橡胶粒子对物理性质起到很强的正面效应。     

朗盛颗粒化橡胶开拓全新市场机遇

朗盛集团旗下位于德国Marl的三元乙丙橡胶颗粒化工厂已正式运营投产。这是该公司首次能够以颗粒的形式（颗粒尺寸为2～3mm）在下属工厂生产并销售该种橡胶。朗盛已向该工厂投资了数百万欧元,其产能达每小时3—5t。     

橡胶颗粒表面改性及对水泥砂浆强度的影响研究

以水玻璃和NaOH为橡胶颗粒表面改性剂,比较了两种改性剂改性增强橡胶颗粒-水泥砂浆强度的效果,并考察了水玻璃的模数和浓度对橡胶颗粒表面改性增强水泥砂浆效果的影响.通过SEM和FT-IR分析了NaOH和水玻璃表面改性橡胶颗粒的机理.实验结果表明:水玻璃表面改性橡胶颗粒增强橡胶颗粒-水泥砂浆的效果优于NaOH.水玻璃改性的橡胶颗粒,表面更加粗糙,覆盖块状凝胶凸起,同时表面存在-OH基团和Si-O基团更利于橡胶颗粒与水泥水化产物的结合.随水玻璃模数、浓度增大,水玻璃改性橡胶颗粒-水泥砂浆试样强度逐渐增大,模数对改性效果的影响更明显.     

The separate roles of phase structure and interfacial adhesion in toughening a brittle polymer

The effects of rubber particle size and rubber/matrix adhesion on the impact properties of a brittle polymer have been separated using polystyrene (PS)/acrylonitrile-butadiene rubber (NBR) as a model system in which interfacial chemical reaction could be controlled. It has been proven that the interfacial adhesion between the rubber phase and the PS matrix not only greatly aids in reducing the rubber particle size but also plays a further role in improving the impact properties of the matrix polymer. The impact energies of PS/NBR blends with interfacial chemical bonding are four to ten times as high as those without interfacial bonding for the same average rubber particle size. However, at temperatures below the glass transition temperature of the rubber, there is no difference in impact energies with or without interfacial chemical bonding. It has been found that the optimum rubber particle size for toughening PS is influenced by interfacial adhesion. Smaller optimum rubber particle size is observed for blends with greater amounts of interfacial chemical bonding.     

Characterization of rubber particle size distribution of high-impact polystyrene using low-angle laser light scattering

A new application of low-angle laser light scattering has led to a new instrument capable of characterizing the rubber particle size distribution of high-impact polystyrene (HIPS) containing particles as small as 0.1 μ. Rubber particle size distributions of several HIPS resins have been characterized, and the particle size ranking of resins using light scattering parallels the ranking of resins using photomicroscopy. Several solvents have been employed to suspend the HIPS rubber particles for the scattering determination. Swelling of the rubber phase has been found to be relatively insensitive to variations in rubber phase crosslinking when methyl ethyl ketone is used to suspend the rubber particles. Particle swelling in methyl ethyl ketone does not detract from the usefulness of the light scattering method for HIPS rubber particle size characterization.     

橡胶粒子尺寸对ABS树脂性能的影响

通过乳液聚合制备了橡胶粒子尺寸为64～420 nm的丙烯腈-丁二烯-苯乙烯(ABS)共聚物.然后将其与SAN-T树脂熔融共混制备橡胶质量分数为15%的ABS树脂.研究了橡胶粒子尺寸对ABS树脂力学性能影响和材料内部形态结构.结果表明:随着橡胶粒子尺寸的增加ABS树脂的冲击韧性提高.当橡胶粒子尺寸在320 nm时,拉伸强度达到最大,ABS树脂的综合性能达到最好.粒子尺寸在64～110 nm时,橡胶粒子在基体内部发生团聚,材料发生脆性断裂.当橡胶粒子尺寸在216～420 nm时,材料主要以韧性断裂为主,发生脆韧转变.具有双峰分布ABS-110nm/ABS-275 nm共混物大、小橡胶粒子间发生明显的协同作用.     

Influence of solvent contents on the rubber‐phase particle size distribution of high‐impact polystyrene

High‐impact polystyrene (HIPS) was prepared by the bulk or low‐solvent polymerization of styrene in the presence of dissolved rubber and characterized to measure the dispersed particle size of the rubber phase. Before preparation, the prepolymerization time was established by measuring the evolution of particle size distribution of the dispersed phase as a function of reaction time. The measurement technique by laser light scattering was found to be efficient enough not only to lead to the right prepolymerization time but also to predict rubber‐phase particle size distribution. Polymerization experiments were then conducted to investigate the effect of solvent contents on the particle size distribution of the rubber phase, in which ethylbenzene was introduced as a solvent at levels of 0, 3, 10, and 15%. As the solvent content increased, the size of rubber‐phase particles initially increased, reaching a maximum, and then decreased. It is speculated that a decrease in the molecular weight of the matrix, a decrease in the viscosity ratio between polybutadiene to polystyrene phases, and a change in rubber morphology all contributed to the change in the rubber particle size of HIPS. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3672–3679, 2003     

高转化率乳聚丁苯橡胶聚合过程中乳液相对分子质量分布与粒径分布考察

采用中石油吉化分公司乳聚丁苯橡胶高转化率大生产配方,考察了实验室聚合反应釜聚合反应单体转化率随反应时间的变化,采用激光粒度分析仪和凝胶渗透色谱仪测定了聚合反应不同单体转化率的胶乳的粒径分布与分子质量分布,结果表明：胶乳粒径呈正态分布,粒径主要集中分布在0.1μm附近,胶乳的平均粒径随反应时间的延长逐渐增大,但是增加的幅度越来越小;聚合反应时间在11 h前（即转化率小于72%）,胶乳的重均分子质量、Z均分子质量一直增大,而数均分子质量变化无明显规律;而分子质量分布宽度指数随反应的进行变小,表明调整的高转化率配方合成的丁苯橡胶可有效改善聚合生成的胶乳粒径分布。     

Rubber particle agglomeration phenomena in acrylonitrile-butadiene-styrene (ABS) polymers. I. Structure-property relationships study on rubber particle agglomeration and molded surface appearance

The effects of molecular structures of ABS fabricated under a severe molding condition on rubber particle agglomeration and molded specular gloss were studied. An agglomeration index (N_P) obtained by measuring particle size was used to determine the degree of rubber particle agglomeration. It was found that as graft level decreased, agglomeration increased. The rubber particle agglomeration also increased when graft molecular weight was increased. Lowering the particle size also led to a higher degree of agglomeration. Furthermore, increasing the compositional acrylonitrile mismatch between the grafted and matrix styrene-acrylonitrile copolymers increased the rubber particle agglomeration. Molecular structures that increased rubber particle agglomeration decreased the molded gloss. © 1996 John Wiley & Sons, Inc.     

不同引发剂对应马来酸酐改性橡胶混凝土抗冻性能研究

通过不同引发剂对马来酸酐改性橡胶并制备橡胶混凝土,对不同引发剂、橡胶粒径和橡胶掺量对抗冻性能影响进行研究,并通过SEM对冻融前后橡胶混凝土界面进行分析.试验结果表明,以DCP作为引发剂抗冻效果最佳,且橡胶粉粒径为60目、掺量为15%时,橡胶混凝土抗冻性能最佳.经200次冻融循环后,橡胶混凝土内部结构相对松散,结构发生破坏.     

Quantitative characterization of dispersed particle size,size distribution,and matrix ligament thickness in polypropylene blended with metallocene ethylene–octene copolymers

The average rubber particle size, size distribution, and matrix ligament thickness between particles in polypropylene blends containing metallocene catalyzed ethylene–octene copolymers have been quantitatively analyzed, as functions of blend composition and phase viscosity ratio. Comparison has been made between experimental data and those predicted from a number of theoretical models. All blends showed two‐phase morphology, with interestingly a bimodal distribution of the rubber particle size. The ranges and averages of rubber particle size were mainly determined by blend composition and viscosity ratio between the phases, irrespective of comonomer content along the rubber chains. The logarithmic relationship between the matrix ligament thickness and rubber concentration was observed. The values of ligament thickness obtained from the experiments and theoretical models were not in agreement. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2140–2149, 2001     

研磨改性废轮胎热解炭黑及其应用研究

本文主要研究采用研磨的方法改性CBp,并将其应用到丁苯橡胶中,对比考察了不同研磨时间的CBp、未改性CBp、N774的粒径分布差异及在丁苯橡胶中的性能差异。研究结果表明：研磨的方法可有效减小CBp的粒径,有助于其在橡胶中更好的分散,且研磨时间越长,炭黑粒子粒径越小,门尼粘度越大,扭矩差越大。研磨后的CBp补强的丁苯橡胶的拉伸强度、撕裂强度、300%定伸强度、硬度得到有效提高,综合改性效果良好。