国内聚苯乙烯行业现状和加入WTO的影响

分析了国内聚苯乙烯行业现状，包括国内PS生产、需求、市场占有率及价格预测以及影响PS的价格因素等，指出了我国加入WTO后PS行业受到的影响和相应对策。     

纳米铝填充聚苯乙烯熔融纺丝及其性能研究

采用分散聚合法合成了聚苯乙烯(PS)及在PS中掺杂纳米铝(Al NPs)的PS/Al NPs复合材料,采用熔融纺丝法制备了PS及PS/Al NPs纤维,并对其结构与性能进行了研究。结果表明:重均相对分子质量(Mw)为(5~25)×104的PS,在220~270℃熔融纺丝,制得PS纤维直径可达25μm,断裂强度为1.2 c N/dtex,断裂伸长率为4.8%;PS/Al NPs复合材料中Al NPs在PS中分散均匀,PS内部中的Al NPs抗氧化能力较好;与相同Mw的PS纤维比较,PS/Al NPs纤维的玻璃化转变温度提高了4℃,断裂强度提高了4.1%,断裂伸长率提高了13.3%。     

聚苯乙烯市场的供需现状及发展预测

介绍了目前国际和国内聚苯乙烯市场的状况,对入世后我国PS产品的市场竞争力进行了论证分析,并对发展我国的PS工业提出建议.     

我国须加大废弃PS泡沫塑料回收再利用

<正>目前全球每年约产生废弃聚苯乙烯(PS)泡沫塑料580万t,其中我国每年产生约180万t,除少数发达国家外,其他国家的废弃PS泡沫材料并未得到有效回收。据不完全统计,目前北欧国家和日本PS泡沫塑料回收再生利用率为72%,韩国PS泡沫塑料回收再生利用率为64%,而其余国家和地区的PS泡沫塑料回收再生利用率仅为10%～30%。在我国,由于回收机制还不够完     

我国PS版的现状

胶印是当今印刷的主要方式,PS版是胶印印刷的主要耗材。我国PS版的规模化生产是从1985年二胶引进美国宝丽光技术、英国杜马克设备的一条年产200万m2的PS版生产线投产开始的。20年来,我国已发展成PS版生产和使用的大国,全国已有大大小小的PS版生产厂60多家,2004年PS版生产能力已达1.3亿m2,全国PS版总产量1.2亿m2,不但可满足我国印刷制版业的需求,还有10%的产品出口海外。据报道,到2005年底,全国PS版的总的生产能力将达2亿m2。     

膨润土杂化改性聚丙烯共混体系性能研究

以乙醇为分散介质,过氧化二苯甲酰为引发剂,硫代硫酸钠为催化剂,合成了与聚丙烯具有良好复配性能的膨润土杂化改性聚苯乙烯材料(PS/H)。研究了PP/PS、PP/(PS/H)共混体系的性能。结果表明:原位悬浮聚合产物粒子中存在PS及有机改性的膨润土H,且膨润土在聚合产物中分散性良好;对于PP/PS和PP/(PS/H)共混体系,PS及PS/H的加入影响了PP的结晶形态,使共混体系结晶速率增加,相同比例的共混体系PP/(PS/H)对于PP/PS而言,其熔融峰位置向低温偏移,体系熔点略低,其结晶峰位置向高温偏移,结晶温度有较明显的提高;动态温度扫描结果显示,共混体系的表观粘度随着温度的升高而降低,同等PS含量下,由于杂化体系中膨润土的引入,PP/(PS/H)体系的表观粘度高于PP/PS体系;XRD测试结果表明,在熔融共混加工过程中聚合物链没有插层到膨润土片层中。     

印刷制版用N_2等离子体蓝紫光源的实验研究

我国的印刷制版行业目前正处于从传统PS版向计算机直接制版(Computertoplate)技术转变的进程之中,PS版的产销量十分可观,在CTP技术中继续使用传统的PS版对我国印刷包装行业意义重大。实现传统PS版的CTP技术关键在于解决曝光光源问题。本文采用连续直流源空心阴极放电方式产生氮气等离子体蓝紫光源,成功地对一种超感度重氮萘醌系PS版进行曝光,从注入功率、放电气压等方面探讨了氮气等离子光源的最佳工作条件,在工作气压70Pa、放电电压580V、电流1.8A下获得了0.46mW/cm2的蓝紫光输出。气体放电光源还可轻易实现高频大功率脉冲输出,本研究结果表明,新型空心阴极氮气等离子体光源在实现PS版CTP技术方面具有一定的发展前景。     

国内外聚苯乙烯共混改性研究进展

综述了国内外聚苯乙烯（PS）树脂的生产、应用及新品种的开发情况,重点讨论了PS的各种增韧方法,分析了低顺式聚丁二烯橡胶、高顺式聚丁二烯橡胶、复合橡胶、三元乙丙橡胶、纳米复合材料及其他材料对PS的改性,对PS及其相关技术开发提出了建议。     

聚苯乙烯市场的供需现状及发展预测

介绍了目前国际和国内聚苯乙烯市场的状况，对入世后我国PS产品的市场竞争力进行了论证分析，并对发展我国的PS工业提出建议。     

PS/PA6/CB共混体系导电性能研究

在哈克流变仪中将炭黑(CB)与聚苯乙烯(PS)、尼龙6(PA6)共混,研究了CB在PS/PA6/CB共混体系中的分散情况及CB含量和PS与PA6的质量比对PS/PA6/CB共混体系导电性能、微观形态的影响。结果表明,CB在PS/PA6/CB共混体系中只分散在PA6中;PS/PA6/CB共混体系的导电性能随着CB含量的增加而增强,CB的体积分数在20%~40%时,PS/PA6/CB共混体系的电导率增幅明显;PS、PA6两相的微观尺寸随CB含量增加而变小;PS/PA6/CB共混体系中PS与PA6质量比约为80/20时,PS/PA6/CB共混体系的导电性能最好。     

Anomalous transport of hydrocarbons in polystyrene

The transport kinetics and equilibrium concentrations of n-pentane at high penetrant activities in cast, annealed polystyrene were determined and compared with similar measurements in biaxially-oriented polystyrene. The rate of Case II (relaxation-controlled) sorption in biaxially-oriented polystyrene is three to four times faster than the sorption rate in cast, annealed polystyrene. The Case II sorption process in biaxially-oriented polystyrene is more highly temperature dependent than in cast, annealed film. The higher activation energies coupled with the larger relaxation-controlled sorption rates in biaxially-oriented polystyrene imply the involvement of larger polymer segments in the rate controlling polymer relaxations. The sorption in cast, annealed polystyrene was a position-dependent relaxation controlled transport process; in contrast the sorption in biaxially oriented polystyrene, albeit relaxation-controlled, was not position dependent. The position dependence of the Case II sorption appears to be a consequence of the presence of residual benzene in the film which accelerates the rate-determining relaxations. Desorption measurements at very low penetrant activities were quite similar for both biaxially oriented and cast, annealed polystyrene. The desorption kinetics were Fickian and were only a weak function of polymer orientation at these low activities.     

A study on new polymerization technology of styrene

The classic polymerization technology of polystyrene is a high‐cost and nonfriendly environmental technology. Furthermore, the weight‐average molecular weight of polystyrene is hard to enhance up to 400,000 in the classic polymerization technology. The disadvantages limit the growth rate of polystyrene. The solution for increasing the growth rate of polystyrene lies in new technology. The reactive extrusion process of polystyrene was studied in detail and the whole reactive extrusion process of polystyrene was obtained. By means of controlling the flow rate of styrene and the initiator and the screw rotational speed, samples of polystyrene with different molecular weights were synthesized by the twin‐screw extruder. The properties of synthesized polystyrene with different molecular weights were studied; the mechanic properties of polystyrene will increase with an increase of the weight average molecular weight of polystyrene. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2130–2135, 2002     

Low molecular weight block copolymers as plasticizers for polystyrene

Polystyrene‐b‐alkyl, polystyrene‐b‐polybutadiene‐b‐polystyrene, and polystyrene‐b‐poly(propylene glycol)monotridecyl ether were synthesized using macro initiators and atom transfer radical polymerization or by esterifications of homopolymers. The aim was a maximum molecular weight of 4 kg/mol and minimum polystyrene content of 50 w/w %, which by us is predicted as the limits for solubility of polystyrene‐b‐alkyl in polystyrene. DSC showed polystyrene was plasticized, as seen by a reduction in glass transition temperature, by block copolymers consisting of a polystyrene block with molecular weight of approximately 1 kg/mol and an alkyl block with a molecular weight of approximately of 0.3 kg/mol. The efficiency of the block copolymers as plasticizers increases with decreasing molecular weight and polystyrene content. In addition, polystyrene‐b‐alkyl is found to be an efficient plasticizer also for polystyrene‐b‐polyisoprene‐b‐polystyrene (SIS) block copolymers. The end use properties of SIS plasticized with polystyrene‐b‐alkyl, measured as tensile strength, is higher than for SIS plasticized with dioctyl adipate. The polystyrene‐b‐polybutadiene‐b‐polystyrene and polystyrene‐b‐poly(propylene glycol)monotridecyl ether series were only partially soluble in polystyrene and insoluble in the polystyrene phase of SIS. For the lowest molecular weight samples, this leads to measurable plasticization of polystyrene but no plasticization of SIS. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 981–991, 2005     

交联型聚苯乙烯微球的制备

采用无皂乳液聚合法制备了单分散亚微米级聚苯乙烯微球。考查了偶联剂的种类和用量对聚苯乙烯微球形貌、粒径、粒径分布及溶解性能的影响。结果表明：采用N,N-亚甲基双丙烯酰胺为偶联剂制备的聚苯乙烯微球为亚微米级,并且呈现单分散性;增加偶联剂的用量,聚苯乙烯微球的粒径先减小后增大,单分散指数变大。FT-IR谱图表明合成了聚苯乙烯微球。     

以聚苯乙烯为模板制备有序大孔氧化铝

采用少皂乳液聚合法成功制备了单分散的聚苯乙烯微球,以微球自组装后的聚苯乙烯胶体晶体为大孔模板,铝溶胶为前驱体填充模板,干燥焙烧除去模板后制备了氧化铝载体。用激光粒度仪、扫描电镜、X射线衍射和氮气吸脱附对聚苯乙烯胶体晶体和氧化铝载体进行了表征。结果表明:少皂乳液聚合法制备的聚苯乙烯微球具有粒径较小(100~350 nm)、单分散性好(0.005)、收率高(约80%)等优点;自组装的胶体晶体呈规则有序排列,微球表面光滑洁净,并以此为模板成功制备了具有三维有序结构的、大孔孔径可调的氧化铝材料。     

Ionomers made from copolymers with uniform grafts

Summary Carboxylic acid-containing graft copolymers with uniform polystyrene grafts were synthesized by copolymerization of methacrylate-terminated polystyrene macromers, acrylic acid and butyl scrylate. The graft copolymers were neutralized with metal ions in solution or in melt to form ionomers, which were characterized by IR, TEM and dynamic mechanical analysis. TEM photographs showed that there appeared three phases in the ionomers, namely polystyrene domains, ion clusters and continueous phase of polybutyl acrylate, while dynamic mechanical analysis indicated the phase separation of polystyrene and ion-containing polyacrylate.     

聚苯乙烯树脂的手性修饰

以交联聚苯乙烯为原料树脂,二苯甲酰酒石酸酐为傅—克酰基化反应的酰化试剂合成手性树脂,通过红外光谱和元素分析对该手性树脂进行了表征,研究了溶剂、催化剂、反应温度、反应时间对该手性修饰树脂增重率的影响。     

Blue Light Emission from Pulsed Laser Ablated Polystyrene

Thus far, pulsed laser ablation has been widely applied to the surface modification of polymers, but no work has been done for fluorescence performance of polystyrene ablated by pulsed laser. In this paper, a 1064 nm pulsed laser was used to ablate polystyrene. Compared to non-ablated polystyrene, the ablated polystyrene gave off obvious blue light under UV lamp irradiation. The morphology and structure of ablated and non-ablated polystyrene were studied by Fluorescence spectroscopy and IR. The results showed that the maximal emission wavelength of ablated polystyrene was 403 nm, which showed that blue light emission occurred. Because of ablation the surface chemical structure of polystyrene was changed and new C=C existed in the surface of ablated polystyrene. And the photoluminescent material was dissolvable, not cross-linked.     

Effects of Polystyrene Block Content on Morphology and Adhesion Property of Polystyrene Block Copolymer

Effects of polystyrene block content on adhesion property and phase structure of polystyrene block copolymers were investigated. Polystyrene-block-polyisoprene-block-polystyrene triblock and polystyrene-block-polyisoprene diblock copolymers with different polystyrene block contents in the range from 13 to 35 wt% were used. In the case of the low polystyrene block content (below 16 wt%), a sea-island structure was observed: near-spherical polystyrene domains having a mean diameter of about 20 nm were dispersed in polyisoprene matrix. The phase structure changed from a sea-island structure to a cylindrical structure with an increase of polystyrene block content (over 18 wt%). Peel strength decreased with an increase of polystyrene block content and the pure triblock copolymers had lower peel strength than their blends with the diblock copolymers. Pulse nuclear magnetic resonance studies indicated that molecular mobility of polyisoprene phase decreased with an increase of polystyrene block content, and the molecular mobility was lower in the pure triblock than in the blend. Thus, the peel strength was found to be related to molecular mobility. The adhesion strength of the block copolymer depended on the molecular mobility: high molecular mobility can promote interfacial adhesion.     

The Effect of Nitric Acid Oxidization Treatment on the Interface of Carbon Fiber-Reinforced Thermoplastic Polystyrene Composite

The quality of interfacial interaction is dictated by the surface chemistry of the carbon fibers and the composition of the matrix. The composition of polystyrene was modified by the addition of maleic anhydride (MAH) grafted polystyrene. The surface properties of the various matrix formulations were characterised by contact angle. Carbon fibers were modified by oxidation in nitric acid. The surface composition of the carbon fibers was characterized. The interaction between modified polystyrene and the carbon fibers was studied by single fiber pull-out tests. The best adhesion behavior was achieved between polystyrene containing grafted MAH and nitric acid oxidation carbon fibers. The addition of MAH-grafted polystyrene to the unmodified polystyrene caused the interfacial shear strength to increase. The apparent interfacial shear strength of this fiber-matrix combination allowed for the utilisation of 100% of the yield tensile strength of polystyrene.