bPE-g-MAH对PC/bPE共混物力学性能与断面形态结构的影响

利用熔融接枝法制备了双峰聚乙烯接枝马来酸酐(bPE-g-MAH),将其用作聚碳酸酯/双峰聚乙烯(PC/bPE)共混物的增容剂。通过力学性能测试和扫描电镜分析,研究了bPE-g-MAH对共混物相容性和力学性能的影响。结果表明:bPE-g-MAH的加入使得PC和bPE两相的界面黏合作用增强,使PC/bPE共混物的冲击强度显著提高。     

基于模糊PID的微型拉伸试验机研究

基于有色金属材料在工业CT环境下同时进行拉伸和断层扫描的特殊试验要求,首次采用非金属材料聚碳酸酯作为试验机机架,设计了一种微型材料拉伸试验机.采用伺服电机作为加载动力源,为解决伺服电机及传动机构的非线性影响加载精度问题,设计了模糊PID控制算法,以满足加载实时控制的精度要求.仿真和实验证明了新型微型试验机方案的有效性.     

Thermally induced redistribution and degradation of bisphenol-A polycarbonate fractions in open and closed systems

Thermally induced chain-scission and redistribution reactions in as-polymerized and fractionated bisphenol-A polycarbonate (PC) materials made by melt-transesterification and interfacial polymerization were studied at temperatures between 200 and 300 °C in open systems, where volatile reaction products are continuously removed, and in closed systems, where these products are retained. Under the applied conditions, PC made via interfacial polymerization shows no measurable susceptibility towards redistribution. This is the result of an extremely low concentration of hydroxyl end-groups. Upon similar thermal treatment, PC made by melt-transesterification undergoes fast redistribution which leads to post-condensation in open systems and strong changes of molecular weight distributions (MWDs) for fractions in all cases. Redistribution effects were visualized through changes in the MWD of mixed fractions. The initial stages of redistribution were simulated using a Monte Carlo method based on a random sampling technique. From comparison between experimental and simulation results, it can be concluded that approximately half a percent of all carbonate linkages is involved in a redistribution reaction per minute at 250 °C for the studied samples.     

大型生物法燃料乙醇副产二氧化碳有效利用途径的探讨

探讨了大型生物法燃料乙醇项目副产二氧化碳的有效利用途径，提出了利用二氧化碳生产碳酸二甲酯（DMC），再利用DMC生产碳酸二苯酯（DPC），最后利用DPC生产聚碳酸酯的技术路线，从而使二氧化碳作为原料广泛地应用于有机合成，医药，化工，塑料等行业。     

Electrochemical Fabrication of Metallic Nanowires and Metal Oxide Nanopores

A nuclear track etched polycarbonate membrane filter with numerous cylindrical nanopores was applied as a nanoporous template for growing metallic nanowires. Nickel, cobalt, and iron nanowires were electrodeposited into the cylindrical nanopores. Cathodic polarization curves were measured to determine an optimum condition for growing nanowires. The shape of nanowires was observed using scanning electron microscope (SEM) and the crystal structure was analyzed using transmission electron microscopy (TEM). Diameter and length of nanowires corresponded to those of nanopores and each nanowire was composed of a single crystal. Anodized aluminum oxide films were also fabricated as a novel nanoporous template. The pore length and diameter was controlled changing anodizing conditions. Ordering behavior of nanopores array in an anodized aluminum oxide film was also investigated to make a novel nanoporous template with a highly ordered honeycomb array of nanopores.     

马来酸酐接枝ABS及其应用

采用熔融法研究了马来酸酐（ＭＡＨ）接枝ＡＢＳ。结果表明：马来酸酐接枝率随ＭＡＨ添加量或引发剂过氧化二异丙苯（ＤＣＰ）的添加量垢增加而提高，但是添加量过多时，接枝率增加速率变慢；ＡＢＳ接枝马来酸酐后，冲击性能明显下降，但拉伸性能变化不大；马来酸酐接枝改性ＡＢＳ，增容ＡＢＳ／ＰＣ合金共湿物，可提高合金的缺口抗冲击强度大１．５～２．５倍。     

朝阳1号聚碳酸酯中径迹退火研究

本文报道了朝阳1号聚碳酸酯固体径迹探测器中^208Pb和^93Nb离子径迹的退火行为。给出了退火温度和时间对退火速率的影响，温度对VT的影响。^208Pb和^95Nb的退火活化能分别为0．891eV和0.352eV。     

The high strain rate compressive behaviour of polycarbonate and polyvinylidene difluoride

Measurements are presented of the compressive stress–strain behaviour of polycarbonate (PC) and polyvinylidene difluoride (PVDF) at strain rates from 10⁻⁴ to 10⁴ s⁻¹ at room temperature, and temperatures from −50 to +150 °C at 10³ s⁻¹. These results, obtained using a split Hopkinson pressure bar and Instron testing machine, are supported by dynamic mechanical analysis (DMA) measurements on the materials. Previous researchers have observed that the yield stress of these materials is bilinearly dependent on the logarithm of strain rate. The data presented here show that the bilinearity is due to the movement of low order transitions in the materials, so that they occur at temperatures above room temperature at the higher strain rates. In particular, these transitions are the β transition in PC, and the glass transition in PVDF. In addition, Appendix A presents measurements of a high strain rate Poisson's ratio of polycarbonate and its evolution with strain.     

Adhesion and Scratch Resistance of Polycarbonate Films on Ferroplate Substrates: Effect of γ-APS Primers

The influence of γ-aminopropyltriethoxysilane (γ-APS) primers on the adhesion and scratch resistance of polycarbonate (PC) films on ferroplate substrates was determined from the critical normal loads at which debonding of the films from the substrates occurred during scratch testing. The critical load was a strong function of the concentration of the aqueous solutions from which the γ-APS primers were adsorbed and of the thickness of the primer films. Thus, the critical normal load increased from 0.09 ± 0.02 N to 0.31 ± 0.07 N as the concentration of the γ-APS solutions increased from 0.05% to 0.2%, respectively. However, the critical load increased only slightly as the solution concentration increased beyond 0.2%. The increase in critical load as concentration of γ-APS solutions increased was related to the formation of an interphase involving chemical reaction and physical entanglement of PC and γ-APS molecules. The critical load for debonding of PC films from the substrates also depended strongly on the temperature at which the γ-APS films were dried before application of the PC films. Thus, the critical normal loads for debonding were 0.31 ± 0.07, 0.20 ± 0.02, and 0.05 ± 0.01 N for γ-APS films that were dried for 15 min at room temperature, 60°C, or 110°C, respectively. The decrease in critical load with increasing drying temperature was attributed to the greater cross-link density in γ-APS films that were dried at elevated temperatures, which limited interdiffusion and physical entanglement of PC and γ-APS molecules. High reaction temperature of γ-APS and PC induced a fragmentation of amine. However, it also increased the probability of amines to react with carbonate because of increasing mobility of PC chains. Optimization of these two factors was required to obtain the greatest adhesion and scratch resistance. Chemical reactions occurring between PC films and γ-APS primers were investigated by reflection–absorption infrared spectroscopy (RAIR) and X-ray photoelectron spectroscopy (XPS) using diphenyl carbonate (DPC) as a model compound. The carbonyl absorption band of neat DPC was observed at 1780 cm^?1. However, two carbonyl bands were observed at 1738 and 1652 cm^?1 in RAIR spectra of γ-APS films that were reacted with DPC and were assigned to urethane and urea groups, respectively. XPS results revealed that urethane was the main reaction product between DPC and γ-APS. It was concluded that urethane groups formed by the reaction of PC with γ-APS were responsible for adhesion and scratch resistance of PC to ferroplate substrates that were primed with γ-APS.