高透明抗冲击聚苯乙烯树脂的研制：I.结构与性能

用自由基接枝聚合法研究了不同增韧剂制备透明抗冲聚苯乙烯，发现只有采用高苯乙烯含量的丁二烯，苯惭烯嵌段共聚物作为增韧剂，才能得到透明好的抗冲击聚苯乙烯，所得高透明抗冲击聚苯乙烯的透光率与Ｋ树脂相当，抗冲击性能优于Ｋ树脂。     

透明高抗冲聚苯乙烯树脂的工业化试验

在5kt／a高抗冲聚苯乙烯树脂装置上,以1,1-双(叔丁基过氧基)环己烷为引发剂、苯乙烯为单体、丁二烯-苯乙烯嵌段共聚物(简称K树脂)为增韧剂,采用自由基聚合工艺生产了透明高抗冲聚苯乙烯(HT-IPS)树脂,考察了HT-IPS树脂的微观结构、相对分子质量及其分布、流变性能、接枝反应程度、物理机械性能和光学性能,讨论了影响HT-IPS树脂结构及性能的因素。结果表明,HT-IPS树脂具有微观相分离结构,聚丁二烯链段为分散相、聚苯乙烯链段为连续相;HT-IPS树脂的流动性能略差于高抗冲聚苯乙烯树脂,且随着K树脂用量的增加,其流动性能变差,K树脂用量应控制在15份以下;在聚丁二烯链段的主链和侧链均发生了接枝反应,HT-IPS树脂具有较高的弯曲强度、弹性模量和拉伸强度,其光学性能、流变性能良好,但冲击强度较低,扯断伸长率较小。     

高透明抗冲聚苯乙烯中试研究

在连续本体聚苯乙烯中试装置上对高透明抗冲聚苯乙烯树脂进行了研究。结果表明,中试产品冲击性能与增韧剂相当,比小试产品稍差。小试产品、中试产品及增韧剂具有相似的互穿网络结构。     

星型高透明抗冲击丁苯树脂结构与性能研究

以苯乙烯、丁二烯为单体,正丁基锂为引发剂,环氧大豆油为偶联剂,通过阴离子聚合制备了星型高透明抗冲击丁苯树脂.考察了相对分子质量、无规过渡段含量和终止方式对星型高透明抗冲击丁苯树脂性能的影响.结果表明:随着基础相对分子质量增加,星型高透明抗冲击丁苯树脂悬臂梁冲击强度增加,熔体流动速率迅速降低;随着无规过渡段含量的降低,星...     

抗冲改性剂

抗冲击苯乙烯树脂组成物；丙烯酸类抗冲改性剂及改善热稳定性的PVC组成物；流动性良好的高冲击强度树脂组成物；高透明耐冲击抗静电聚碳酸酯树脂组成物；增硬聚氯乙烯用抗冲改性剂；透明丙烯酸树脂用抗冲改性剂。     

曹妃甸工业区化学产业园重点招商项目介绍(二)

<正>7年产2万t K树脂项目K树脂是苯乙烯含量较高的丁二烯-苯乙烯嵌段共聚物,具有优良的透明性、抗冲击性和无毒性,是其他树脂重要而优异的改性材料,同时也是一种可广泛单独使用的热塑性树脂,主要用于包装、日用塑料制品、医疗器具、玩具制造等领域。目前国内K树脂工业化生产刚刚开始,市场处于快速发展阶段,产能不到3万t/a,2008年、     

聚苯乙烯的抗冲击改进

针对纯聚苯乙烯的抗冲击强度太差,采用固体聚苯乙烯和橡胶机械掺合、将橡胶掺进聚苯乙烯的乳浊液中和将橡胶加在苯乙烯单体的溶液中进行聚合来改进抗冲击强度。对聚苯乙烯的工艺流程的装置作出系统的归纳和苯乙烯聚合的抗冲击进行改进的研究,使得橡胶粒子能更好的吸收冲击能和防止裂缝增长,从而改进了聚苯乙烯的抗冲击强度,最终可以制得抗冲击强度高的产品。     

国外动态

耐洗涤的透明苯乙烯——丙烯酸酯共聚物，用于薄壁制件的高流动PBT，与其它树脂粘合的苯乙烯TPE，抗冲击抗静电PC配混料，易流动PBT，性能提高的光固化立体造型用树脂，用于软质泡沫的高熔体强度PP……     

增韧阻燃高抗冲聚苯乙烯的研制

采用接枝(乙烯/丙烯/二烯)共聚物(EPDM)、K胶、(苯乙烯/丁二烯/苯乙烯)共聚物(SBS)和粉末丁腈橡胶(NBR)为高分子材料增韧剂,十溴联苯醚和三氧化二锑为阻燃剂,高抗冲聚苯乙烯(HIPS)为基体树脂通过共混、挤出过程制得增韧阻燃HIPS复合材料。对该复合材料的力学性能、阻燃性能进行测试,分析了该复合材料的微观结构,并讨论了复合材料的增韧机理。结果表明,SBS比其它3种增韧剂的增韧作用明显,并有良好的阻燃效果。     

增韧剂BE/BA/PCC对聚苯乙烯力学性能的影响

研究了增韧剂BE/BA/PCC中非离子表面活性剂(BE)、丙烯酸丁酯(BA)及纳米碳酸钙(PCC)的比例及其在苯乙烯聚合后期的添加量对生成的聚苯乙烯(PS)的力学性能的影响。发现增韧剂的原料质量比BE/BA/PCC为1∶4∶95,添加量为苯乙烯聚合物(改性PS树脂)的5%时,改性PS树脂的力学性能最好。     

Impact behavior and fracture morphology of acrylonitrile–butadiene–styrene resins toughened by linear random styrene–isoprene–butadiene rubber

A novel toughening modifier, styrene–isoprene–butadiene rubber (SIBR), was used to improve the impact resistance and toughness of acrylonitrile–butadiene–styrene (ABS) resin via bulk polymerization. For comparison, two kinds of ABS samples were prepared: ABS‐1 was toughened by a conventional modifier (a low‐cis polybutadiene rubber/styrene–butadiene block copolymer), and ABS‐2 was toughened by SIBR. The mechanical properties, microstructures of the as‐prepared materials, and fracture surface morphology of the specimens after impact were studied by instrumented notched Izod impact tests and tensile tests, transmission electron microscopy, and scanning electron microscopy, respectively. The mechanical test results show that ABS‐2 had a much higher impact strength and elongation at break than ABS‐1. The microscopic results suggested that fracture resistance of ABS‐1 only depended on voids, shear yielding, and few crazing, which resulted in less ductile fracture behavior. Compared with ABS‐1, ABS toughened by linear random SIBR (ABS‐2) displayed the synergistic toughening effect of crazing and shear yielding, which could absorb and dissipate massive energy, and presented high ductile fracture behavior. These results were also confirmed by instrumented impact tests. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Styrene–diene–lactone block copolymers

By use of butyllithium as initiator and by incremental addition of monomers, block polymers of styrene, butadiene, and lactone can be prepared. Polymerization of ?-caprolactone involves the displacement by base on the carbonyl carbon with the formation of an alkoxide endgroup. To polymerize lactone with poly(butadienyllithium), it is best to convert the carbon–lithium chain ends to alkoxide ends first. Styrene–butadiene–lactone terpolymers of high butadiene contents are thermoplastic rubbers. They have raw tensile strength equal to S–B–S triblock copolymer. Caprolactone-containing samples have unusually good ozone resistance; those prepared with the β-lactone of 2,2,4-trimethyl-3-hydroxy-3-pentenoic acid have much improved hot tensile strength. Terpolymers of low butadiene content are clear thermoplastic resins. Polymer of 20–20–60 (styrene–butadiene–caprolactone) polymer has raw properties similar to those of balata. It has high tensile, high tear strength, and similar hardness at room temperature, but higher softening point. Polymer alloy formed by mixing styrene–acrylonitrile copolymer and styrene butadiene capro lactone terpolymer has high tensile strength and excellent Izod impact. It compares favorably with ABS resin made by latex graft polymerization.     

PVC/MBS共混物的形态及力学性能

采用种子乳液聚合方法,在聚丁二烯乳胶粒子上接枝甲基丙烯酸甲酯（MMA）和苯乙烯（St）,制得MBS核壳接枝共聚物,并将其作为增韧剂与聚氯乙烯（PVC）共混制备PVC/MBS共混物。考察了接枝不同MMA和St含量的MBS在PVC中的分散状态及其对PVC/MBS共混物力学性能。结果表明,当MBS壳层中MMA含量增加时,MBS粒子在PVC基体中的分散状态被改善;PVC/MBS共混物的冲击强度随之增加,冲击强度最高时为1117.74 J/m;当MBS中接枝少量St时,PVC/MBS共混物呈现韧性断裂,冲击值最高时为1039.33 J/m;当MBS接枝大量St时,会产生内包容现象,不利于提高PVC共混物的冲击强度。     

Synthesis and mechanical properties of high impact polystyrene with in situ bulk polymerization toughened by one‐pot Nd‐based styrene–isoprene–butadiene terpolymer rubber

High impact polystyrene (HIPS) resins were obtained with in situ bulk polymerization toughened by styrene–isoprene–butadiene terpolymer rubber (SIBR). SIBR prepolymer was prepared through selective polymerization of styrene (St), isoprene (Ip), and butadiene (Bd) in St with [Nd]/[Al]/[Cl] catalyst. Nd‐based catalyst exhibited more favorable activity toward conjugated diene other than St, resulting in St solution of random SIBR with high cis‐1,4 stereoregularity and low St content, which was directly exposed to the free radical polymerization of St to generate HIPS. Effect of toughened rubber and the initiators [difunctional (D2) and trifunctional (T3)] were examined to attain HIPS possessing mechanical properties as follow: impact strength, 0.9–24.8 kJ/m²; tensile strength, 16.0–27.5 MPa; and elongation at break, 7.4–107.0%. Increasing SIBR matrix in HIPS improved the impact strength and decreased tensile strength. The fracture surface morphologies of HIPS specimens were studied by notched impact tests and scanning electron microscopy (SEM), illustrating that the incremental SIBR matrix presented synergistic toughening effect of crazing to enhance the ductile fracture behavior. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43979.     

The toughness and morphology of (chlorinated poly[vinyl chloride])/(methyl methacrylate‐butadiene‐styrene) blends

A series of methyl methacrylate‐butadiene‐styrene (MBS) graft copolymers were synthesized via seeded emulsion polymerization techniques by grafting styrene and methyl methacrylate on poly(butadiene‐co‐styrene) (SBR) particles. The chlorinated poly(vinyl chloride) (CPVC)/MBS blends were obtained by melting MBS graft copolymers with CPVC resin, and the effect of the core/shell ratio of MBS graft copolymer and SBR content of CPVC/MBS blends on the mechanical properties and morphology of CPVC/MBS blends was studied. The results showed that, with the increase in the core/shell ratio, the impact strength of the blend increased and then decreased. It was found that, when the core/shell ratio was 50/50, the impact strength was about 155 J/m, and the tensile strength evidently increased. The toughness of the CPVC/MBS blend was closely related to the SBR content of the blend, and with the increasing of SBR content of blend, the impact strength of the blend increased. The morphology of CPVC/MBS blends was observed via scanning electron microscopy. Scanning electron microscopy indicated that the toughness of CPVC/MBS blend was consistence with the dispersion of MBS graft copolymers in the CPVC matrix. J. VINYL ADDIT. TECHNOL., 22:501–505, 2016. © 2015 Society of Plastics Engineers     

Synergistic effect of dual rubber system in toughening styrene maleic anhydride copolymers

Styrene maleic anhydride (SMA) copolymers were toughened by blending with two distinctly different rubber modifiers: styrene‐butadiene‐styrene (SBS) block copolymer and methacrylated butadiene‐styrene emulsion‐made graft copolymer (MBS). The modifiers were used both individually and in combination for the examination of their roles in toughening SMA. SMA was miscible with poly(methylmethacrylate) shell of MBS, whereas it was partially miscible with the polystyrene (PS) phase of SBS. When 40–50% of SBS was used in blends, the PS phase of SBS became immiscible with SMA. SBS did not improve the Izod impact strength of SMA appreciably. A prominent synergistic toughening effect was experimentally observed when SBS and MBS were used in combination in brittle SMA. This effect may be attributed to the fact that the large SBS particles initiate crazes and small MBS particles with good adhesion to SMA matrix improve the ligament thickness, which may play a critical role in craze growth and termination. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2260–2267, 2003     

丁苯嵌段共聚物的合成

以环己烷为溶剂、苯乙烯(St)和丁二烯(Bd)为单体、正丁基锂(n-BuLi)为引发剂、四氢呋喃(THF)为结构调节剂,γ-(2,3-环氧丙氧)丙基三甲氧基硅烷为偶合剂,通过活性负离子溶液聚合得到了丁苯嵌段共聚物。研究了杂质对阴离子聚合的影响,苯乙烯转化率、温度与聚合时间的关系,丁二烯转化率与聚合时间的关系,丁二烯、苯乙烯共聚时转化率与聚合时间的关系,单体比及偶合工艺条件的确定,"游离"聚苯乙烯(PS)、"游离"丁苯共聚物对冲击强度的影响。结果表明,总单体比(St/Bd)为72/28～76/24(质量比)、无规段单体比(St/Bd*)为55/45～62/38(质量比)、THF为单体总质量的0.6%～1.0%时,在(75±5)℃下聚合,(85±5)℃下偶合可得到力学性能较好的丁苯嵌段共聚物,Mw=2.493×105,Mn=8.99×104,相对分子质量分布为2.77。     

Development of AAS resin by the emulsion–suspension polymerization method

In order to improve the weatherability of acryonitrile—styrene—butadiene rubber graft polymer (ABS resin), an attempt was made to develop a resin (AAS resin) in which acrylic rubber of good weatherability was used instead of butadiene rubber. First, by copolymerizing dicyclopentenyl-methacrylate (DCP-MA,3%) with butyl acrylate, crosslinked acrylic rubber was obtained. This also introduced grafting sites into the rubber. Next, methods of graft copolymerizing styrene and acrylonitrile with this rubber were examined. An emulsion–suspension polymerization method was developed in which the initial stage of the polymerization, emulsion polymerization, changed into suspension polymerization during the process. By this method of polymerization, rubber particles were combined and enlarged, bringing about a graft-type resin with high impact resistance. This polymerization method is industrially useful because particle-shaped resins are obtained without the need of a salting-out process. The AAS resin, obtained in this way, has much improved weatherability over ABS resin and shows strength equal to that of ABS resin. © 1992 John Wiley & Sons, Inc.     

本体原位法制备高抗冲聚苯乙烯 Ⅰ.引发剂的影响

以稀土催化体系磷酸酯钕盐/氢化二异丁基铝/一氯二乙基铝在苯乙烯中选择性地使丁二烯聚合,并且以自由基引发剂过氧化苯甲酰、1,1-二(叔丁基过氧基)环己烷、3,6,9-三甲基-3,6,9-三乙基-1,4,7-三过氧烷(TETMTPA)或2,2-二(4,4-二叔丁基过氧环己基)丙烷引发聚丁二烯和苯乙烯聚合制备高抗冲聚苯乙烯(HIPS).在相同的官能团浓度下,TETMTPA引发的聚合反应速率最快,制备的HIPS冲击强度最高.随着TETMTPA用量从0.01 phr提高至0.05 phr,聚合反应速率增加,HIPS的悬臂梁缺口冲击强度从120.6 J/m降至72.4 J/m.     

苯乙烯在MBS中的结合方式对PVC/MBS性能的影响

以乳液聚合法合成了化学组成恒定的具有核-壳结构的(甲基丙烯酸甲酯/丁二烯/苯乙烯)共聚物(MBS),通过改变原料及其配比,使苯乙烯(St)在MBS中以共聚或接枝方式结合,用动态力学热分析仪研究了MBS内耗与温度的关系。将MBS与聚氯乙烯(PVC)共混,研究了St结合方式对共混物冲击韧性及增韧机理的影响,结果表明,随着MBS核中St含量的增加,PVC/MBS共混物的脆-韧转变向高温移动;当St仅以接枝的方式结合时,橡胶粒子的空洞化及剪切屈服是主要的增韧机理,当St仅以共聚方式结合时,剪切屈服是主要的增韧机理。