废旧电视机外壳塑料中十溴联苯醚的溶剂法分离

以d-柠檬烯为溶剂、正丙醇为沉淀剂建立了溶剂法再生废旧电视机外壳塑料(主要成分为高抗冲聚苯乙烯,HIPS)的新工艺,考察了外壳塑料溶液中十溴联苯醚在固-液两相的分布特征及影响因素,探讨了反溶剂沉淀过程中十溴联苯醚的转移机制,提出了减少十溴联苯醚进入再生HIPS产品的措施,通过实验确立了从废旧电视机外壳塑料中分离十溴联苯醚的工艺条件. 当电视机外壳塑料浓度为20%,使用管式离心分离机,在温度30℃、转速12000 r/min下能去除溶液中87.7%的十溴联苯醚;每100 mL离心液补加40 mL柠檬烯溶解十溴联苯醚颗粒后,再用等体积正丙醇在50℃下沉淀HIPS,所得再生塑料的多溴联苯醚总含量低于0.1%,十溴联苯醚的脱除率超过99%.     

盐湖卤水镁锂沉淀分离工艺研究

采用氨水和氢氧化钠作为沉淀剂,对高镁锂比卤水进行镁的二次沉淀分离以及母液蒸发浓缩提锂工艺进行研究。实验结果表明:常温下,采用质量分数为10%的氨水作为沉淀剂,可使卤水除镁率达到88.6%,实现卤水中镁锂的初步分离;在此基础上,采用氢氧化钠溶液作为沉淀剂,控制浓度为8 mol/L的氢氧化钠溶液的滴加速度为3 mL/min、反应时间为20 min、溶液终点pH=12.5、搅拌转速为120 r/min,采用漏斗过滤氢氧化镁沉淀,卤水的除镁率可达到99.8%。母液经蒸发浓缩析出氯化铵和氯化钠晶体,使锂得到富集。     

硫化钠沉淀法从含铑溶液中富集铑工艺研究

用硫化钠作沉淀剂,从含铑强酸性水溶液中沉淀富集铑金属。通过实验确定了影响铑沉淀率的诸多因素,如沉淀剂加入量、沉淀温度、沉淀剂硫化钠加料速度、陈化时间及搅拌速度等。结果表明,当沉淀剂硫化钠与铑的物质的量比为10、沉淀温度为100 ℃、硫化钠加入速度为5 mL/min、陈化时间为1 h、搅拌速度为600 r/min时,铑沉淀率达到最大,铑沉淀率最高为99%以上。富集后溶液铑含量低于1 mg/kg,铑富集效果明显。     

氢氧化铝表面改性及在高抗冲聚苯乙烯中的应用

选用钛酸酯偶联剂对高性能纳米氢氧化铝(ATH)进行表面改性,以改善其在高抗冲聚苯乙烯(HIPS)中的分散性。利用透射电镜(TEM)和傅立叶红外光谱仪(FTIR)表征了高性能纳米氢氧化铝的改性效果,研究了改性条件对高性能纳米氢氧化铝/高抗冲聚苯乙烯复合材料性能的影响。结果表明,在偶联剂质量分数1.5%,改性时间20 min,改性温度85℃的条件下,高性能纳米氢氧化铝/高抗冲聚苯乙烯复合材料的综合性能较好。改性后高性能纳米氢氧化铝的分散性得以有效的改善,其表面确实包覆了偶联剂分子。     

水油乳液预聚再悬浮聚合的高抗冲聚苯乙烯

现在市场上大多数高抗冲聚苯乙烯都是由橡胶—苯乙烯溶液共聚而成的。橡胶—苯乙烯溶液在有搅拌的本体预聚中转化12—40％,然后或者在不搅拌的情况下进行本体聚合,或者在带搅拌的水中进行悬浮聚合。共聚过程中搅拌程度对最终产品的性质有深远影响。高速搅拌所得的产品中凝胶含量低,橡胶粒度小。反之,如果聚合过程中搅拌速度较低,则所得产品中的凝胶含量高,橡胶粘度也大。橡胶粒度和凝胶含量是决定高抗聚苯乙烯物理性能的两     

液体硫酸铝沉淀法除铁

采用有机沉淀剂A作为沉淀剂,用沉淀的方法来除去液体硫酸铝中的铁,达到提纯液体硫酸铝的目的。对于操作过程中的沉淀剂加入量、操作温度和反应时间进行了条件试验。在沉淀剂A的溶液和硫酸铝溶液质量比为8×10-2、操作温度为25℃、反应时间为60~75 min时,液体硫酸铝(ρ为80 g/L)中铁含量小于30.0×10-6(质量分数)。     

工业废水处理及回收锌的工艺探讨

介绍了用空气氧化低价铁,再分别用石灰和碳酸钠中和沉淀锌冶炼过程产生的酸性废水中铁和锌的工艺,研究了溶液pH值、空气流速、沉淀剂种类及反应时间对铁去除率、锌损失率及沉锌率的影响。研究结果表明,氧化沉淀除铁的最佳反应条件为pH值3.5,空气通入流速20 mL/min,反应时间4 h,此时铁去除率为99.54%,锌损失率为2.50%;沉淀提锌较适宜的沉淀剂为碳酸钠,最佳反应条件为pH值7.5,反应时间30 min,此时沉锌率为99.60%,干燥后沉淀中锌质量分数为52.03%,折合碳酸锌的质量分数高达99.77%。     

无卤阻燃高抗冲聚苯乙烯的研制

采用不同类型和不同用量的无卤阻燃剂与高抗冲聚苯乙烯熔融共混,制得无卤阻燃高抗冲聚苯乙烯。考察了阻燃剂的品种和用量对高抗冲聚苯乙烯阻燃性能的影响,介绍了各阻燃剂的基本阻燃机理,测试了无卤阻燃高抗冲聚苯乙烯的氧指数和燃烧热。结果表明,氰尿酸三聚氰胺盐复合阻燃剂对高抗冲聚苯乙烯有良好的阻燃效果。     

聚合磷酸酯类阻燃剂

将聚苯乙烯干燥,溶于PCl_3中,在AlCl_3存在下,在50℃搅拌3小时,得到含磷聚合物沉淀。在0℃的C_2H_2Cl_2中用CH_3OH处理此沉淀,得到的聚合亚磷酸酯在高抗冲聚笨乙烯中有阻燃作用。     

碱式碳酸锌生产工艺改进

研究了以菱锌矿为原料通过酸浸、除杂、中和、沉淀、干燥制备碱式碳酸锌和活性氧化锌的生产工艺。以有机沉淀剂SC-1和有机螯合剂QK-8为除杂剂，除铁、锰、重金属等杂质，经过滤、中和、沉淀和干燥得碱式碳酸锌。最佳工艺条件为：有机沉淀剂用量1％（有机沉淀剂占硫酸锌溶液体积分数），有机螯合剂用量1％（有机螯合剂占硫酸锌溶液体积分数）。碱式碳酸锌在600～650℃煅烧3～4h，得到氧化锌质量分数为98.3％～98.5％的活性氧化锌。     

HIPS回料改性树脂的研究和应用

研究了HIPS回料的性能,研制了一种HIPS回料改性树脂,在HIPS回料中添加改性剂使HIPS回料改性树脂的性能得到极大的提高。试验结果表明:HIPS回料改性树脂的性能可以达到或超过HIPS新料的性能。在HIPS回料中添加SBS树脂,可以明显提高冲击强度和断裂伸长率,而拉伸强度和洛氏硬度有所下降;添加K树脂可以提高改性树脂的熔体流动速率;添加纳米蒙脱土可以提高改性树脂的拉伸强度、断裂伸长率、冲击强度、弯曲强度、弯曲模量、热变形温度、维卡软化点和洛氏硬度以及熔体流动速率。采用SBS树脂和K树脂以及纳米蒙脱土等材料组成的配方体系,可以制得符合使用要求的HIPS回料改性树脂,经生产应用表明,HIPS回料改性树脂的性能能够满足实际使用要求。     

Isothermal crystallization, melting behavior and crystalline morphology of syndiotactic polystyrene blends with highly-impact polystyrene

Syndiotactic polystyrene (sPS) blends with highly-impact polystyrene (HIPS) were prepared with a twin-screw extruder. Isothermal crystallization, melting behavior and crystalline morphology of sPS in sPS/HIPS blends were investigated by differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD) and polarized optical microscopy (POM). Experimental results indicated that the isothermal crystallization behavior of sPS in its blends not only depended on the melting temperature and crystallization temperature, but also on the HIPS content. Addition of HIPS restricted the crystallization of sPS melted at 320 °C. For sPS melted at 280 °C, addition of low HIPS content (10 wt% and 30 wt%) facilitated the crystallization of sPS and the formation of more content of α-crystal. However, addition of high HIPS content (50 wt% and 70 wt%) restricted the crystallization of sPS and facilitated the formation of β-crystal. More content of β-crystal was formed with increase of the melting and crystallization temperature. However, α-crystal could be obtained at low crystallization temperature for the specimens melted at high temperature. Addition of high HIPS content resulted in the formation of sPS spherulites with less perfection.     

Viscoelastic melt behavior of poly(2,6-dimethyl-1,4-phenylene oxide), high-impact polystyrene,and a 35–65 blend

The viscoelastic melt behavior of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO

1 PPO is a registered trademark of the General Electric Company.

resin), high-impact polystyrene (HIPS), and a 35–65 blend of these polymers has been characterized by measuring the steady shear viscosity and primary normal stress difference and the dynamic storage and loss moduli as functions of shear rate or frequency and temperature. Time–temperature superpositioning was used to generate master curves of each type of data for a reference temperature of 260°C. This procedure required five different empirical shift factors for each material. These shift factors show large differences between PPO resin and HIPS and exhibited large deviations from the WLF equation with universal constants. This result suggests that the temperature dependence of the relaxation processes in PPO resin is significantly different from the temperature dependence of HIPS relaxations. Flow activation energies computed from the viscosity data for PPO resin are much higher and more shear sensitive than those calculated for HIPS. The computed relaxation spectra clearly display the effect of long-time relaxation mechanisms associated with PPO molecules when compared to HIPS. The 35–65 blend exhibits general rheological compatibility with material parameters and responses intermediate between PPO resin and HIPS. This result is indicative of a high degree of segmental mixing for the two components in the blend.     

Synthesis,structure, and properties of high‐impact polystyrene/octavinyl polyhedral oligomeric silsesquioxane nanocomposites

The organic–inorganic hybrid nanocomposites from high‐impact polystyrene/octavinyl polyhedral oligomeric silsesquioxane (HIPS/POSS) containing various percentages of POSS were prepared by free radical polymerization and characterized by Fourier transform infrared spectroscopy (FTIR), ¹H‐NMR, thermal gravity analysis (TGA), X‐ray diffraction (XRD), and transmission electron microscopy (TEM). The octavinyl POSS has formed covalent bond connected PS‐POSS hybrid with polystyrene. POSS can well disperse in the composites at the composition of 0.5 and 1 wt%. The mechanical properties and thermostability of HIPS/POSS nanocomposites were significantly improved. The tensile strength, the izod impact strength, and the elongation at break of the nanocomposite containing 1 wt% of POSS was increased, respectively, by 15.73%, 75.62%, and 72.71% in comparison with pristine HIPS. The thermal decomposition temperature of HIPS/POSS (1 wt% of POSS) was 33°C higher than that of pristine HIPS. The HIPS/POSS nanocomposites showed great potential for applications in many fields, such as electric appliance and automotive trim. POLYM. COMPOS. 37:1049–1055, 2016. © 2014 Society of Plastics Engineers     

Nanocomposites based on high impact polystyrene/silver nanoparticles: Effect of silver nanoparticles concentration on the reaction evolution,morphology, and impact strength

Nanocomposites based on high impact polystyrene (HIPS) and silver nanoparticles (AgNPs) were synthesized via in situ bulk‐suspension polymerization adding a colloidal suspension of AgNPs in styrene from the beginning of the reaction. The concentrations of AgNPs in the final nanocomposites were 0, 0.025, 0.10, and 1.0 wt%. The rate of polymerization and free radicals concentration were found to decrease with increasing AgNPs concentration. For nanocomposites with 0.025 and 0.10 wt% of AgNPs, the phenomenon of phase inversion (PI) during the mass polymerization occurred within the same range as that for the blank HIPS. Further, the impact strength of these nanocomposites did not present any changes as compared to the blank HIPS. However, there was no sign of the PI phenomenon in the case of 1.0 wt% of AgNPs, due to a decrease in the amount of free and graft polystyrene onto the rubber chain as the free radicals concentration diminishes with an increase in AgNPs. In this case the impact strength doubles the values of the blank HIPS due to the presence of a interpenetrated polymer network of crosslinked grafted rubber and polystyrene (PS) instead of the formation of a defined morphology. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers     

Experimental investigation into the selective laser sintering of high‐impact polystyrene

High‐impact polystyrene (HIPS) was used as selective laser sintering (SLS) material. The sintering parameters and the properties of sintered parts were investigated. The results show that sintered parts, which have good dimensional accuracy and good mechanical properties, can be fabricated with wide ranges of laser energy and bed temperature. To apply HIPS parts as functional parts, a reinforcement method, in which the sintered HIPS parts were postprocessed by infiltrating with epoxy resin, were suggested. The properties of the parts after postprocess were also studied. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

超韧聚苯乙烯的制备工艺研究

以高抗冲聚苯乙烯（HIPS）为基体树脂，采用双螺杆挤出机研究了抗冲击改性剂SBS对HIPS的增韧效果，探讨了制备工艺条件对超韧HIPS材料性能的影响。结果显示，SBS对HIPS具有优异的增韧效果，当其用量达到40份时，能使HIPS体系的常温简支梁缺口冲击强度达到42．1kJ／m^2。通过添加高效流变控制剂体系，使HIPS／SBS体系的流动性大大提高。采用低剪切的螺杆组合，低的机头压力，中低的螺杆转速和半饥饿喂料法，在较低的温度下制备所得的超韧HIPS材料具有优异的低温韧性和优良的综合性能。     

Water absorption and mechanical properties of PP/HIPS hybrid composites filled with wood flour

Water absorption and mechanical performance of the injection‐molded hybrid composites prepared from different ratios of two polymer blends (57 wt%), two compatibilizers (3 wt%), and two wood species (40 wt%) were investigated. The ratio of polypropylene and high‐impact polystyrene (HIPS) gradually increased in the blend (from 10 to 30 wt%). Styrene–ethylene–butylene–styreneblock copolymer and maleic anhydride‐grafted PP (MAPP) were used as compatibilizer (3 wt%). The shore D hardness of the PP/wood composites was improved by the incorporation of the HIPS. The HIPS/wood flour composites showed higher tensile modulus but lower tensile strength than the PP/wood composites. The water resistance of the PP/wood composites decreased with increasing HIPS content. POLYM. COMPOS., 38:863–869, 2017. © 2015 Society of Plastics Engineers     

低烟无卤阻燃HIPS的研究

采用熔融法制备包括有机蒙脱土（OMMT）、红磷（RP）和酚醛树脂（PFR）体系的阻燃高抗冲聚苯乙烯（HIPS）复合材料，用基于耗氧原理的锥形量热仪研究复合材料的阻燃性能，用扫描电子显微镜观察了复合材料燃烧残余物的微观结构形态。结果表明，与纯HIPS相比，制备的HIPS／OMMT复合阻燃材料阻燃性能有所提高，但提高幅度有限；与HIPS／OMMT复合阻燃材料相比，添加RP和PFR的阻燃RP／PFR／HIPS／OMMT复合材料的热释放速率及其峰值、质量损失速率和生烟速率等燃烧性能参数继续降低，且火灾性能指数大幅提高，表现出低烟和高效的阻燃特点。     

高光泽PS的影响因素

研究了不同的树脂和助剂在高抗冲聚苯乙烯（HIPS）和通用级聚苯乙烯（GPPS）中对光泽度的影响。主要比较了GPPS、低分子量SBS和液体聚丁二烯对高光HIPS光泽度的影响,另外还研究了K树脂、低分子量SBS和液体聚丁二烯对GPPS光泽度的影响。结果表明通过液体聚丁二烯与K树脂复配可以提高GPPS的冲击性能。