高耐热型系列ABS／PC合金的研制

介绍了高耐热型、高耐热高抗冲击型及高耐热阻燃型ABS/PC合金的研制和应用。     

聚碳酸酯中双酚 A 的毒性及迁移规律研究进展

介绍了双酚 A 的理化性质和毒性,分析了食品包装材料中双酚 A 对食品安全的影响及对人体健康的危害性,综述了聚碳酸酯中双酚 A 的迁移机理,以及时间、温度、酸碱度等因素对迁移规律的影响。     

Impact fracture behavior of molecularly orientated polycarbonate sheets

The impact fracture behavior of molecularly orientated polycarbonate (PC) sheets was investigated. The molecular orientation was achieved via a newly developed equal channel angular extrusion (ECAE) process. Improvement in impact fracture propagation resistance was observed in the ECAE processed PC sheets. The improved impact resistance was found to be directly related to the changes in molecular orientation because of ECAE. The unique characteristics of the ECAE process for polymer extrusion are described. The potential benefits of ECAE in enhancing physical and mechanical properties of the extruded PC sheets are discussed. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 2060–2066, 2001     

光学级聚碳酸酯在光盘生产中的缺陷分析

分析了光学级聚碳酸酯在光盘生产中的缺陷、产生原因及补救措施。对实际生产具有一定的指导作用。     

聚碳酸酯的技术进展和市场开拓

介绍了聚碳酸酯的生产和技术进展情况,总结了聚碳酸酯的主要应用领域,阐述了世界需求的增速和生产能力分布,最后提出了加快发展聚碳酸酯技术的几点意见。     

Key properties to understand the performance of polycarbonate reprocessed by injection molding

The reprocessing of injection‐molded polycarbonate was studied in an attempt to understand the physical background for the variation of its performance upon sequential molding cycles. The effect of reprocessing on different properties of the moldings and the regrind is presented and discussed. A quantitative analysis of the Fourier transform IR spectra indicates that phenol and carbon dioxide are released during the initial cycles, probably due to molecular scission near the chain ends. Most of the results obtained agree well with the findings reported elsewhere. Essentially, the molecular weight, the free volume, and the specific volume were found to be critical properties for understanding the global performance of the moldings. Both the free volume and the reciprocal of the molecular weight depend linearly on the number of reprocessing cycles. Based on these properties, it is possible to develop relatively simple relations to estimate the variation of the rheological, optical, and mechanical properties with the number of reprocessing operations. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1393–1400, 2000     

Palmitoylated cellulose nanocrystal/polycarbonate composite with high mechanical performance and good transparency

To fabricate polycarbonate (PC) composites with high mechanical and optical properties, PC composite films reinforced by cellulose nanocrystals esterified using palmitoyl chloride (palmitoylated cellulose nanocrystal [PAL-CNCs]) were fabricated by casting-evaporation and characterized by several techniques. It was shown that the PAL-CNCs with a substitution degree of 0.43 and the crystalline index of 53.3% were better dispersed in chloroform and tetrahydrofuran, and achieved a water contact angle of 81.0°. The crystallite size and crystalline index of the PC in the composite film significantly increased to more than 5.2 nm and 51.5%, respectively, after the incorporation of the PAL-CNCs. The PC composite film had an increase of 91.4% in tensile strength, 84.1% in Young's modulus, and a decrease of 5% in impact strength. Meanwhile, its UV–Vis-light transmittance was above 90%. Therefore, the palmitoylated -CNCs were a better candidate for engineering PC composites with high mechanical performance and transparency.     

Ce cooperated layered double oxide with enhanced base sites activity for the synthesis of polycarbonate diols

The development of highly efficient alkaline catalysts with abundant base sites is of paramount importance for the synthesis of polycarbonate diols (PCDLs). And the application of heterogeneous catalysts is an effective strategy to address the effect of residual catalysts on the quality of PCDLs. Here, Ce cooperated layered double oxide (LDO-Ce) was used as a catalyst for the preparation of PCDLs via transesterification between dimethyl carbonate (DMC) and 1,4-butanediol (BDO). CO₂ temperature-programmed desorption (CO₂-TPD) profiles demonstrated that the introduction of Ce led to an increase in strong base sites of LDO-Ce, thus endowing LDO-Ce with excellent catalytic performance. Besides, LDO-Ce possessed satisfactory specific surface area and pore size. A possible catalytic mechanism was proposed to illustrate the transesterification process. The effects of the reaction conditions on the hydroxyl value, yield, and BDO conversion were further investigated in detail. The yield of PCDLs with a hydroxyl value of 112.2 mg KOH/g (corresponding to a number average molecular weight [M_n] of 1000 g/mol) was 92.44% under its optimum reaction conditions (w (catalyst) = 0.5%, n(DMC)/n(BDO) = 1.25, T-_{transesterification} = 130°C, t-_{transesterification} = 5 h, T-_{polycondensation} = 170°C, t-_{polycondensation} = 4 h, P-_{polycondensation} = 10 kPa). Moreover, LDO-Ce was easily removed after the transesterification process (Step 1), ensuring the quality of PCDLs, and it was recycled three times without significant loss of catalytic activity.     

Lifetime Prediction and Aging Mechanism of Glass Fiber Reinforced Acrylate-Styrene-Acrylonitrile/Polycarbonate Composite under Hygrothermal Conditions

The development of fifth-generation technology has resulted in increased demand for materials with low dielectric losses and superior thermal and mechanical properties. However, ensuring the widespread use of such materials by investigating their aging mechanisms and operating lifetimes remains challenging. In this study, a glass-fiber (GF)-reinforced acrylate-styrene-acrylonitrile/polycarbonate (ASA/GF/PC) composite is designed and comprehensively investigated its aging behavior, mechanism, and service lifetime under long-term hygrothermal conditions. Based on the general Peck model, the composite maintains a high level of quality for over 10 years, including under harsh conditions of 40 °C and 80% relative humidity. The aging mechanism is primarily ascribed to cracking between the GF fibers and matrix, the breaking of chemical bonds, the generation of new cross-linked domains, and physical aging. These findings provide valuable insights into the long-term utilization of ASA/GF/PC composites in harsh environments.