苯乙烯类嵌段共聚物对IR/CR共混物形态结构的影响

考察了苯乙烯类嵌段共聚物对ＩＲ／ＣＲ二元共混物相态结构及粒子尺寸的影响。结果表明，加入苯乙烯类嵌段共聚物可有效改善ＩＲ／ＣＲ共混物的分散状态，在任何组成下均可降低分散相粒子尺寸，促进体系均匀分散，其中苯乙烯－异戊二烯共聚物的效果最为理想，其最佳用量为３～７份。     

水解酸化-SBR法处理生物制药废水

对采用水解酸化-SBR法处理生物制药废水的调试运行作了详细说明。工程实践表明，该工艺对处理有机物浓度高、水质水量波动大的生物制药废水是切实可行的，出水水质可达到国家污水综合排放标准一级标准．剩余污泥也得到有效处理处置。该工艺结构简单，操作简便，占地面积小，运行效果稳定，具有推广应用价值。     

Phase Behavior and Mechanical Properties of Siloxane-Urethane Copolymer

Two series of siloxane-urethane copolymers were prepared from polydimethylsiloxane (PDMS) with a molecular weight of 1000 or 1800 which was used as a soft segment, 4,4′-diphenylmethane diisocyanate (MDI) and 1,4-butanediol (1,4-BD). Differential scanning calorimetry (DSC) demonstrated that the position (T_gs) and breadth (ΔB) of soft-segment glass transition of copolymers remained constant as the hard-segment content increased. Heat capacities at soft-segment glass transition of the copolymer (ΔCp) were 0.195∼0.411 J/g^○C and heat capacities of pure PDMS (ΔCp₀) were 0.571∼0.647 J/g^○C, leading to the various ΔCp/ΔCp₀ ratios. The ΔCp/ΔCp₀ ratios decreased as the increasing of hard-segment content, showing poor phase separation. The FTIR spectrum confirmed the occurrence of hydrogen bonding in ether end-group of pure PDMS. The ether group of the soft segment led to interfacial mixing between soft and hard segments. The tan δ of the soft segment determined by dynamic mechanical testing (DMA) also identified the mixing of soft and hard segments. The mechanical properties of the copolymer were directly related to either the soft and hard segment contents or the chain lengths of soft and hard segments. The hard segment that reinforced the soft segment and interfacial thickness between soft and hard segment dominated the mechanical properties.     

Preparation and properties of high molecular weight poly(1-germa-) or poly(1-sila-cis-pent-3-enes)

High molecular weight poly(1,1-dimethyl-1-germa-cis-pent-3-ene), poly(1,1-diphenyl-1-germa-cis-pent-3-ene), poly(1,1-dimethyl-1-sila-cis-pent-3-ene), and poly(1-methyl-1-phenyl-1-sila-cis-pent-3-ene) have been prepared. The thermal stability of these polymers is found to increase with their molecular weight.     

Optimal process conditions of shrinkage and warpage of thin‐wall parts

Optimal process conditions of thin‐wall injection molding of a cellular phone cover were investigated with the consideration of interaction effects between process parameters. L₂₇ experimental tests based on Taguchi's method were performed, and then Cyclone Scanner, PolyCAD and PolyWorks were used to measure the shrinkage and warpage of the thin‐wall injected parts to determine the optimal process conditions. Based on the results of the analysis of variables and the F‐test, interaction effects for each observed factor were determined. The results indicated that the packing pressure was the most important process parameter affecting the shrinkage and warpage of the thin‐wall part. The optimal process conditions were different for the shrinkage and the warpage. This was because during the injection process, the mechanisms affecting shrinkage or warpage were different. Compared with the results obtained with simplified thin‐wall parts in the literature, it was found that the geometry of a real commercial part did affect the optimal process conditions and the order of influence of process parameters. The optimal process conditions determined by Taguchi's method for reducing the shrinkage and warpage were verified experimentally in this work. Polym. Eng. Sci. 44:917–928, 2004. © 2004 Society of Plastics Engineers.     

Structures and tribological performances of PEEK (poly-ether-ether-ketone)-based coatings designed for tribological application

Driven by economical and ecological reasons, thermoplastic-based coatings become a potential solution for anti-wear purpose. Two coating design concepts, flame spraying and printing PEEK (poly-ether-ether-ketone)-based coatings on Al substrate, were introduced in this paper. An amorphous PEEK coating was obtained by these two techniques. After being annealed, the coating presents a semi-crystalline structure. The friction and wear behaviors of PEEK-based coatings were investigated by means of ball-on-disc tests. The results show that PEEK coatings exhibit an excellent tribological performance with a relatively low coefficient of friction and wear rate. The semi-crystalline PEEK coating exhibits a lower friction coefficient and wear rate than the amorphous one. The additions of micron-sized particles such as SiC and graphite in PEEK coating can improve significantly the coating wear resistance.     

Molecular weight distribution of polyethylene catalyzed by Ziegler–Natta catalyst supported on MgCl2 doped with AlCl3

Ti‐based Ziegler–Natta catalysts supported on MgCl₂ doped with AlCl₃ were prepared by the reaction of MgCl₂/AlCl₃–ethanol adduct with TiCl₄. No AlCl₃ crystallites were found in the AlCl₃‐doped catalysts by WAXD analysis, suggesting that AlCl₃/MgCl₂ solid solution was formed. The effect of doping on the catalyst performance in ethylene polymerization was investigated. The results showed that the catalysts based on AlCl₃‐doped MgCl₂ support exhibited a slightly higher activity than did the MgCl₂‐supported catalyst and the molecular weight distribution (MWD) of polyethylene (PE) markedly increased (from 10.8 to 47.9) with the increase of AlCl₃ content in catalysts. The changes in catalyst's active center distribution were studied based on nonlinear fitting of the polymer GPC curves by multiple Flory functions. It was found that increase of types of active centers by introducing AlCl₃ into the support should be responsible for the broadening of MWD of PE. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1768–1772, 2006     

焙烧硫酸铁铵催化合成季戊四醇双缩苯甲醛

以硫酸铁铵经600℃高温焙烧制得一类新型固体酸催化剂，该催化剂在合成季戊四醇双缩苯甲醛中具有较高的催化活性，其优化条件是：苯甲醛与季戊四醇物质的量比为2．0：1，催化剂用量为5％(以醇的质量为准)，回流温度83℃，反应时间2．5h，在此优化条件下，反应产率为87％。且催化剂容易制备，可连续使用。     

离子色谱法测定配煤、焦炭和焦油中的氯含量

研究了用带电导检测器的离子色谱对配煤、焦炭和焦油中的Cl- 进行测定的方法。在YSA型8126A-4# 阴离子分离柱上用3.5mmol/LNa2CO3、5.3mmol/LNaHCO3做淋洗液对Cl-进行测定,方法简便快速。Cl-的检出限为2×10-6。该法也适用于F-、NO2-、NO3-、SO42-等的测定。     

纯聚酯户外消光粉末涂料的制备

以高黏度、低酸值的含羧基饱和聚酯树脂为基料,以含有缩水甘油基的丙烯酸树脂为消光固化剂制备纯聚酯户外消光粉末涂料。介绍了该涂料的制备工艺,并讨论了原材料和生产条件对产品性能的影响。