治理塑料废弃物新技术途径探讨--专论可降解塑料的研究开发

综述了可降解塑料的研究开发现状及其进展。可降解塑料的降解时控性研究，合成，加工工艺改进以及降低成本的研究，可控光－生物降解的合成降解性研究和一次性使用塑料实用性研究，仍是今后需要深入探讨的重要研究课题。     

塑料及其复合材料的摩擦学

综述了近年来国内外塑料及其复合材料的摩擦学研究的新进展,涉及到PTFE、PEEK、UHMWPE的合金以及塑料复合材料的重点研究领域,指出基于现代材料设计的摩擦学材料设计、塑料在热和应力作用下的蠕变和长期稳定性、塑料梯度功能材料和环保的绿色材料的摩擦学等方面是未来的发展方向。     

一种新型热塑性淀粉衍生物的制备方法

由于淀粉及其衍生物一般都具有可生物降解,无毒或毒性小,原料易得等方面的优势,以淀粉及其衍生物单独,或作为添加剂与塑料等其它材料复合开发可降解等功能性材料的研究愈来愈受到重视。以淀粉衍生物作为添加剂与非降解性塑料等复合制备可降解材料时,淀粉衍生物的热生是一项非常重要的指标。我们介绍一种平均分子量为50万左右,具有良好的热塑性的新型羟丙羟乙基改性淀粉的制备方法,该产品有望单独,或作为添加剂之一与塑料等混炼,开发出可降解性功能材料。     

汽车用废弃塑料的再生利用现状与展望

汽车废弃塑料的再生利用及其产业化可以变废为宝,减少资源浪费和环境污染。本文综述了近年来汽车废弃塑料的分拣回收和再生利用技术的现状。发展高效的废弃塑料分拣设备和高附加值的再生制品是现今研究的重点。结合国内外的行业发展状况,探讨了我国在发展高附加值的再生制品、可循环利用塑料材料和建立再生塑料的质量安全标准上面临的挑战。     

聚合物光盘基板材料

光盘是一种以非接触方式记录/再现信息的信息记录介质,主要由基板、记录层和保护层组成.其中,基板材料所用的光学塑料是光盘生产的主要原材料,对光盘的性能和成本构成至关重要.本文综述了聚合物光盘基板材料的研究现状及其发展趋势.光盘基板材料主要包括传统的聚碳酸酯(PC)、聚甲基丙烯酸甲酯(PMMA)、环氧树脂以及近年发展起来的非晶环烯烃聚合物.研制具有较低的双折射、吸湿性、固化成型收缩率以及较高的存储密度和存储寿命的光盘基板材料是聚合物光盘基板材料的一个重要研究领域.     

聚合物光盘基板材料的研究进展

光盘是一种以非接触方式记录/再现信息的信息记录介质,主要由基板、记录层和保护层组成。其中,基板材料所用的光学塑料是光盘生产的主要原材料,对光盘的性能和成本构成至关重要。本文综述了聚合物光盘基板材料的研究现状及其发展趋势。光盘基板材料主要包括传统的聚碳酸酯（PC）,聚甲基丙烯酸甲酯（PMMA）、环氧树脂以及近年发展起来的非晶环烯烃聚合物。研制具有较低的双折射、吸湿性、固化成型收缩率以及较高的存储密度和存储寿命的光盘基板材料是聚合物光盘基板材料的一个重要研究领域。     

食品接触塑料材料中有害重金属迁移量测定方法综述

塑料在食品接触材料中占有重要地位,通过介绍食品接触塑料材料中重金属危害及来源,总结食品接触塑料材料中有害重金属安全限量,并对目前食品接触塑料材料中有害重金属的迁移测定方法进行综述。开发食品接触材料快速检测方法是今后研究的方向。     

聚乳酸共混改性研究新进展

聚乳酸(PLA)基塑料相比于聚羟基脂肪酸酯、聚氨基酸等生物基塑料具有更佳的抗拉强度、延展性、光泽度和透明度^[1],而相比于传统石油基塑料又具有可完全降解且无毒无害的优点。作为传统石油基塑料的首选替代品,纯PLA塑料也面临着玻璃化转变温度较低、断裂伸长率较差等缺陷,难以完全替代传统石油基材料。因此,自诞生以来,PLA基塑料的改性工作一直是国内外学者的研究热点,其方法主要包括共聚、共混和添加改性剂等。本文主要阐述近些年来PLA共混改性方法的进展,着重分析其方法、特点及应用。最后,对PLA基塑料的发展前景进行了展望。     

白色污染

塑料作为一种新型合成材料,随着人口膨胀、城市发展、科技进步,在其产量和品种不断增多的同时。大量用过被丢弃的塑料制品所带来的“白色污染”,却越来越成为困扰人类社会的一大公害。本文较详细地讨论了塑料及其废弃物对人体及环境的危害以及废塑料的回收、利用、资源化、能源化和与之有关的分解性塑料等问题。     

新型高分子季鏻盐改性抗菌塑料的制备及性能研究

高分子季鏻盐抗菌剂具有安全、高效的特点,使用过程中不会通过皮肤组织进行渗透。本文将实验室自制的新型高分子季鏻盐抗菌剂粉末与低密度聚乙烯(LDPE)基体材料共混,通过熔融挤出法制备了含梯度浓度抗菌剂的抗菌塑料,研究了不同抗菌剂添加浓度对基体材料熔融性质及其抗菌性能的影响,并探讨了抗菌塑料的生物安全性。结果表明,梯度浓度的抗菌剂改性塑料对金黄色葡萄球菌和大肠杆菌均有良好的抗菌效果;生物安全性测试结果表明,抗菌塑料的细胞毒性为0级,说明抗菌塑料具有较高的生物安全性。     

Development of new cyclic olefin polymers for optical uses

New cyclic olefin polymers (COP) with a better balance of properties than those of conventional optical plastics have been developed by using norbornene monomers. The COP are prepared by ring-opening metathesis polymerization of norbornene monomers followed by complete hydrogenation of double bonds. The COP have practically been applied for optical uses such as lenses, prisms and optical discs.     

微孔塑料连续挤出成型研究进展

综述了微孔塑料的性能特点和应用前景,从微孔塑料的单一相溶液的形成、微孔的成核和气泡的长大控制三个方面详细论述了微孔塑料的连续挤出成型的研究进展,并指出了当前的研究方向。     

STUDIES ON HUMAN LENS: I. ORIGIN AND DEVELOPMENT OF FLUORESCENT PIGMENTS

Abstract
Fluorescence spectra of normal mature human lenses have been measured and at least eight species with distinct emission characteristics identified. To determine the specific photochemical and photophysical processes responsible for the origin and development of these fluorophores, emission behavior of the products generated by successive irradiation of young human lenses (3–6 y old) as well as of L-tryptophan solution have been systematically monitored. Fluorescent products that resulted from this irradiation were comparable to many of the fluorophores detected in aged lenses, indicating that light plays a major role in the development of these pigments. In addition to photogenerated species, there are other compounds in human lenses, presumably advanced glycosylated end products, with marked fluorescence properties.
Several oxidation products of tryptophan including N -formylkynurenine or its derivatives, β-carboline or its derivatives, and anthranilic acid have been identified in the mature human lens. The development of several photoproducts also was attributed to endogenous ascorbate-mediated Maillard reaction products, which undergo photoconversion by the visible light. Although some of these chromophores could act as photosensitaizers, the sensitizing efficiency of many are low. Conversely, the near-UV filtering capability of these colored compounds conceivably could protect the vitreous and retina from development of any photochemical lesion.     

STUDIES ON HUMAN LENS: I. ORIGIN AND DEVELOPMENT OF FLUORESCENT PIGMENTS

Fluorescence spectra of normal mature human lenses have been measured and at least eight species with distinct emission characteristics identified. To determine the specific photochemical and photophysical processes responsible for the origin and development of these fluorophores, emission behavior of the products generated by successive irradiation of young human lenses (3-6 y old) as well as of L-tryptophan solution have been systematically monitored. Fluorescent products that resulted from this irradiation were comparable to many of the fluorophores detected in aged lenses, indicating that light plays a major role in the development of these pigments. In addition to photogenerated species, there are other compounds in human lenses, presumably advanced glycosylated end products, with marked fluorescence properties. Several oxidation products of tryptophan including N-formylkynurenine or its derivatives, beta-carboline or its derivatives, and anthranilic acid have been identified in the mature human lens. The development of several photoproducts also was attributed to endogenous ascorbate-mediated Maillard reaction products, which undergo photoconversion by the visible light. Although some of these chromophores could act as photosensitizers, the sensitizing efficiency of many are low. Conversely, the near-UV filtering capability of these colored compounds conceivably could protect the vitreous and retina from development of any photochemical lesion.     

废旧塑料改性再生的研究进展

塑料制品作为一种全球范围内广泛使用的商品,几乎已经渗透到了人类生活中的各个方面。同时,快速累积的废旧塑料对陆地和海洋环境产生了一系列的负面影响。值得注意的是,废旧塑料具有资源和废物双重属性。废旧塑料的回收品质和数量的提高,对于资源的高效利用、可持续发展和环境保护具有重大意义。本文介绍了废旧塑料常用的分选方法,综述了近年来国内外废旧塑料化学改性和物理改性的研究进展,并分析了废旧塑料改性再生所面临的问题。     

新型聚(甲基)丙烯酸酯/盐透明材料的制备及其性能

聚(甲基)丙烯酸酯具有优异的透光性、耐光性和耐候性,广泛用作光学塑料.研制高折射率、高耐热性、低吸湿性的透明高分子材料是近年来光学塑料研究和开发的重点之一.本文介绍了新型聚(甲基)丙烯酸酯/盐透明高分子材料的主要制备方法,即新型单体合成-聚合法、共聚法、共混-聚合法和有机-无机纳米杂化法,并系统地总结了各方法的特点以及所制备的材料的性能,展示了目前应用最为广泛的新型单体合成-聚合法和有机-无机纳米杂化法的潜在的应用前景.     

The application of differential thermal analysis to investigation of thermoplastics

The courses of phenomena occurring in investigated plastics during heating were studied. The plastics specimens have been subjected to investigation before and after heating. Two kinds of plastics being applied in machine constructions Tarnamid T-27 (polyamide 6) and Tarnoform 300 (polyacetale) have been chosen to investigation. The specimens have been subjected to heat treatment in turbine oil at minimum temperature of crystallization: polyamid 6 at 170°C and polyacetal at 140°C. It has been found that during heating in tested plastics endo- and exothermic effects take place and there are some differences for plastics before and after heating. It is possible to calculate the grade of crystallinity on the base of DTA curves. In polyamid 6, in which the polymorphic transformation takes place, the known methods of calculation of degree of crystallinity proves ineffective. Plastics after heating characterize the higher degree of crystallinity grade.     

Modification of construction carbon-reinforced plastics with carbon nanoparticles

The influence of fullerenes and their derivatives on the formation of carbon-reinforced epoxy composites and service characteristics of the construction carbon-reinforced plastics thus formed have been studied. The technology of homogeneous distribution of two- or four-walled carbon nanotubes in the bulk of epoxy oligomers has been developed. A lightning-protective coating on the basis of a carbon-reinforced plastic (CRP) with a carbon-nanotube modifier has been designed. Owing to increased electrical and heat conduction, high thermal destruction temperature, and improved performance characteristics, the designed CRP coating exhibits improved safe damageability under direct stroke and lower weight compared to conventional brass grid lightning-protective coatings.     

Cellular and foamed plastics as separation media A new geometrical form of the solid phase in analytical liquid-solid contact

There has been considerable interest during the last few years in using cellular (foamed) plastics (mainly polyurethanes) either unloaded or as a means of immobilizing hydrophobic organic reagents, powdered ion-exchangers or finely divided precipitates, for the collection and separation of inorganic or organic species from aqueous solution. Foamed plastics with anchored (bonded) functional groups have also been used for the same purpose. It has been realized that the application of cellular plastics is often advantageous not only for quantitative work but also for qualitative and semiquantitative analysis. Methods available on the application of cellular and foamed plastics for the collection, separation and recovery of various inorganic and organic components from aqueous solution are reviewed.