丁苯嵌段共聚物合成中大分子的形成及控制方法

以正丁基锂为引发剂，在环己烷中合成丁二烯-苯乙烯嵌段共聚物(SBS)中的大分子和凝胶产物的形成机理，阐明了聚合反应温度等是产生大分子和凝胶产物的主要原因。为了降低SBS中的大分子和凝胶产物，提出了优选的条件和控制方法。     

马来酸酐熔融接枝SBS及其对PA66的增韧作用

通过加入复合抗氧剂A（酚类），B（亚磷酸酯类）及流动改性剂（液体石蜡），采用热引发熔融接枝法制备马来酸酐接枝SBS，获得了具有较高接枝率（0.52%)和较好熔体流动性且不含凝胶的马来酸酐接枝SBS产物，用该产物增韧PA66，获得了较好的增韧效果。     

SBS改性沥青的老化行为

用红外光谱、凝胶渗透色谱、动态黏弹仪研究了苯乙烯-丁二烯嵌段共聚物(SBS)改性沥青的薄膜烘箱老化行为。结果表明，SBS改性沥青老化后增加了羰基和亚砜基；SBS和沥青的相对分子质量都发生了变化。沥青的相对分子质量增加，相对分子质量分布变宽，SBS特征峰消失；SBS改性沥青老化程度较基质沥青的小，耐低温性能更好；SBS改性沥青老化后，软化点增加，针入度减小，低温延度降低。     

SBS聚合反应偶联效率的研究

介绍苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)的溶液聚合工艺及反应机理,根据产物的凝胶渗透色谱分析得到SBS聚合反应偶联效率等参数,结合聚合反应过程分析偶联效率异常的原因,通过设定适当的偶联剂添加量、调整顺控程序及工艺参数、定期检修偶联剂流量调节阀、控制最终反应温度等措施,有效控制SBS聚合反应的偶联效率,保证SBS产品的质量稳定性。     

SBS的环氧化研究

通过红外光谱对SBS的环氧化产物中环氧基团的存在进行证实。考察了SBS环氧化反应合成条件的影响因素：反应时间，反应温度，SBS的浓度，甲酸，过氧化氢。     

SBS/蒙脱土复合材料的制备及其性能Ⅰ.复合材料的结构

分别采用大分子溶液插层法和大分子熔融插层法制备了苯乙烯-丁二烯-苯乙烯共聚物(SBS),蒙脱土纳米复合材料,采用X射线衍射和透射电子显微镜对材料的结构进行了表征。结果表明,无论是采用大分子溶液插层法还是大分子熔融插层法,都能得到SBS／蒙脱土纳米复合材料。对于溶液插层法,蒙脱土插层剂的种类、SBS牌号对插层效果都有影响：对于熔融插层法,SBS牌号对是否形成插层型纳米复合材料影响最大,淬火对熔融挤出后得到的纳米复合材料无益。星形结构的SBS适宜于采用溶液插层法、线形结构的SBS适宜于采用熔融插层法制备纳米复合材料。     

SBS与SBS/有机蒙脱土复合材料的光化学交联

通过测定交联体系凝胶含量的方法,考察了在紫外光辐照下,苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)进行光化学交联反应的影响因素,并研究了SBS/有机蒙脱土(OMMT)复合材料的光化学交联反应。结果表明,在N2气氛下,提高辐照温度有利于增加SBS交联体系的凝胶含量,且凝胶速率增长较快,辐照温度宜为130℃;与空气气氛比较,N2气氛对SBS的交联反应更有利;与引发剂二苯甲酮相比,安息香二甲醚(BDK)的引发效率高,BDK的最佳质量分数为1%;交联剂宜为异氰尿酸三烯丙酯,当其质量分数为1%时,SBS交联体系的凝胶含量达到最大值;与SBS交联体系相比,SBS/OMMT复合材料交联体系的凝胶速率明显下降。     

热塑性弹性体SBS产品内在质量的对比研究

采用GPS（凝胶渗透色谱）对近年来国内外SBS生产厂商的工业化产品进行了测定，通过测定结果的数据分析及样品GPC谱图的对比，探讨和分析了不同厂商SBS产品的内在质量情况，分析和找出了产品内在质量的差异及影响因素，提出了控制和提高其内在质量所应采取的技术改进方向。     

热塑弹性体SBS气候老化行为规律

SBS是苯乙烯-丁二烯的嵌段共聚物，具有弹性和可塑性双重性能，是一种用途非常广泛的高分子材料，可是由于分子链结构中存在二烯结构，其耐候性极差，在广州户外暴露试验仅只能维持半个月时间，如果掺入适量的稳定剂可以适当延长其户外寿命。户内暴露试验却完全不同，尤其生胶，试验5年或更长时间，还可以再使用。在气候试验的基础上，研讨了二种SBS(线型和星型)的凝胶含量与拉伸性能表征行为的相关性，看来用凝胶含量来衡量SBS户内外老化程度是可行的，可作为力学性能的补充。     

嵌段SBS接枝马来酸酐及马来酸盐的合成及表征

用溶液法合成嵌段SBS接枝马来酸酐(MAH)，控制反应时间、反应温度及MAH用量，得到不同接枝率的产物。用红外光谱及反滴定法定性定量表征了接枝率。结果表明：随反应时间、反应温度和马来酸酐用量的增加，接枝率呈不同增加趋势，其中反应温度对产物接枝率的影响最为显著。分别用NaOH、CaCl2、LaCl3将SBS接枝马来酸酐(SBS—g—MAH)离子化，得到SBS接枝马来酸盐离聚物(SBS—g—MAM)。其耐溶剂性能、吸水性能及对极性基体的粘合性能随离子化程度而发生变化，离聚物具有更好的吸水性及耐溶剂性能。     

SBS改性沥青的基本性能的实验研究

利用SBS对AH-90沥青进行了改性研究,并对改性沥青的软化点、延度、针入度等性能进行表征.结果表明,随着SBS用量的增加,改性沥青的软化点上升,针入度降低,延度增加;但是当SBS用量增加至6%时,针入度降至国家标准以下.因此,SBS用量在4.5%～5.5%时,改性沥青的软化点、延度、针入度等基本性能最好.     

热塑性弹性体SBS的工程开发Ⅴ．万吨级聚合装置SBS产品的性能剖析

对用国内技术建设的万吨级聚合装置生产的５种牌号产品：线型ＳＢＳ１３０１，ＳＢＳ１４０１和星形ＳＢＳ４３０３，ＳＢＳ４４０２及充油３３％的星形ＳＢＳ４４５２２进行了性能剖析。结果表明，国产ＳＢＳ的物理性质、热氧稳定、玻璃化转变温度、微观结构和相态结构与国外同类产品相当，Ｍ＿ｎ可以达到预期要求，说明该开发技术是成功的。     

SBS/MMT共混物改性沥青的稳定性

采用动态剪切流变仪(DSR)与光学显微镜(OM)从动态力学性能及相形态变化的角度研究了苯乙烯-丁二烯-苯乙烯嵌段共聚物与蒙脱土(SBS/MMT)共混物改性沥青的稳定性,同时通过高温贮存稳定性测试对其稳定性作了进一步分析,并对SBS/MMT共混物改性沥青与SBS单独改性沥青及SBS/MMT直接改性沥青的上述性能分别作了比较分析。结果表明,SBS/MMT共混物改性沥青的稳定性整体上较SBS单独改性沥青及SBS/MMT直接改性沥青均有一定程度的提高。     

Styrene‐butadiene‐styrene copolymer compatibilized interfacial modified multiwalled carbon nanotubes with mechanical and piezoresistive properties

In this study, styrene‐butadiene‐styrene tri‐block copolymer/multiwalled carbon nanotubes (SBS/MWNTs) were prepared by means of a solution blending method. To enhance the compatibility between SBS and MWNTs, the SBS grafted MWNTs (SBS‐g‐MWNTs) were used to replace MWNTs. The MWNTs were chemically hydroxylated by the dissolved KOH solution with ethanol as solvent and then reacted with 3‐Aminopropyltriethoxysilane (APTES) to functionalize them with amino groups (MWNT‐NH₂). The SBS‐g‐MWNTs were finally obtained by the reaction of MWNT‐NH₂ and maleic anhydride grafted SBS (MAH‐g‐SBS). The SBS‐g‐MWNTs were characterized by X‐ray photoelectron spectroscopy (XPS), Fourier transform‐infrared spectroscopy (FT‐IR), transmission electron microscopy (TEM), scanning electron microscope (SEM), and thermogravimetric analysis (TGA). The results showed that the SBS molecules were homogeneously bonded onto the surface of the MWNTs, leading to an improvement of the mechanical and electrical properties of SBS/SBS‐g‐MWNTs composites due to the excellent interfacial adhesion and dispersion of SBS‐g‐MWNTs in SBS. A series of continuous tests were carried out to explore the electrical‐mechanical properties of the SBS/SBS‐g‐MWNTs composites. We found out that, near the percolation threshold, the well‐dispersed SBS/SBS‐g‐MWNTs composites showed good piezoresistive characteristics and small mechanical destructions for the development of little deformation under vertical pressure. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42945.     

Reinforcement of styrene-butadiene-styrene tri-block copolymer by multi-walled carbon nanotubes via melt mixing

Styrene-butadiene-styrene tri-block copolymer (SBS) was reinforced with multi-walled carbon nanotubes (MWCNTs) by the interaction through melt mixing. The tensile strength of SBS/MWCNT composites increased with increasing MWCNT content. The interactions between SBS and MWCNTs were characterized by solubility of MWCNTs in tetrahydrofuran, dynamic mechanical analysis, X-ray photoelectron microscope, ultraviolet spectra and transmission electron microscopy. The results showed that there were interactions between MWCNTs and SBS occurred during melt mixing, leading to an improvement of the mechanical properties of SBS/MWCNT composites, as well as the homogeneous dispersion of MWCNTs in SBS. The interactions between MWCNTs and SBS were supposed to consist of the π-π interaction between MWCNTs and the phenyl groups of SBS, as well as the chemical bonding of polybutadiene segments with MWCNTs.     

SBS改性SMC复合材料的研究

本文研究了SBS和SBS/PS体系改性SMC复合材料。实验结果表明,SBS能显著降低SMC的收缩率,使其控制在0.3~0.5‰,同时也改善了SMC材料的力学性能SBS/PS体系的抗收缩效果比SBS好,可以实现零收缩。通过SEM分析,SBS的热膨胀和在SBS-UP界面处形成的微孔是其低收缩化的主要原因。     

Effect of nanoclay on mechanical and thermal properties of triblock SBS (styrene–butadiene–styrene) and its binary blend nanocomposites: comparison between polyethylene and polystyrene

ABSTRACT

In this study, the effect of organo-modified nanoclay (OMMT) on the mechanical and thermal properties of SBS and its blend with low-density polyethylene (LDPE) and polystyrene was investigated. The effect of nanoclay content in the presence of LDPE or PS on the final properties of SBS was studied by tensile tester, dynamic mechanical thermal analysis (DMTA), thermal gravimetric analysis (TGA), X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). Addition of nanoclay affected the mechanical and rheological properties. From X-ray and DMTA results, it was found that due to more affinity between the nanoparticles and the SBS/PE blend, the 2 theta characteristic peak of nanoclay shifted to lower angles. SEM studies showed better dispersion and lower inter-particle distance of nanoparticles in SBS/PE composites in comparison with SBS/PS and SBS composites, confirming the XRD and DMTA results. It can be concluded that nanoclay acts as a compatibilizer in the SBS/LLDPE blend. TGA studies showed higher stability of SBS/PS composites compared to SBS and SBS/PE ones.     

Performance of biomimetic coating modified fiber incorporated styrene butadiene styrene modified asphalt

This study reports the effect of polydopamine bionic coating and γ-methacryloxypropyltrimethoxysilane (KH570) composite modified polyacrylonitrile (PAN) fiber as a secondary modifier on the performance of styrene-butadiene-styrene (SBS) modified asphalt. Dynamic shear rheometer test indicated the complex shear modulu, storage modulus, and loss modulus of modified PAN (KD-PAN) incorporated SBS modified asphalt was increased by 12.4, 20.5, and 11.2%, respectively compared with PAN/SBS modified asphalt. The master curve of G^* of fiber/SBS composite modified asphalt shows that the deformation resistance of KD-PAN/SBS modified asphalt is greater than that of PAN/SBS modified asphalt in the entire loading frequency range. The cone penetration test showed significantly enhanced shear strength of KD-PAN/SBS modified asphalt. The adhesion work test results and SEM images of interface between fiber and SBS modified asphalt revealed that the adhesion effect of KD-PAN and SBS modified asphalt is better than that of PAN and SBS modified asphalt. SEM and AFM images of fiber further showed that the fiber surface becomes rough after modification. The increased surface roughness of KD-PAN facilitated the adherence of SBS modified asphalt to it, which in turn led to the enhanced performance of KD-PAN/SBS composite modified asphalt at the same fiber content and temperature.     

MAH改性SBS的性能研究

研究了马来酸酐（MAH）接枝改性苯乙烯／丁二烯／苯乙烯共聚物（SBS）的方法及其性能。用红外光谱分析确定了MAH已接枝到SBS上,用DSC分析了接枝物的纯度。MAH改性的SBS溶于三元体系溶剂,可制得价廉的胶粘剂,粘接强度高于不用MAH改性的SBS。