EVA和BSC的比较与分析研究

文章介绍了EVA和BSC两种业绩评价方法,通过对其相关概念的引入、EVA和BSC各自适合的企业以及整合的相关性、可行性的分析。     

1 000 t/a书籍装订热熔胶技术经济分析

介绍了书籍装订热熔胶生产工艺及产品的技术指标，对1000t/a生产装置的投资与产品成本进行了核算。分析结果表明，总投资110万元，年利润达266万元。     

EVA基质PTC特性材料制备与导电机理分析

本文简述了以EVA为基质材料制备有机PTC特性材料的实验,实测了样品有关特性,并用非线性回归方法讨论了其导电机理.这对指导温度传感器的设计有一定帮助.     

J-199热熔胶膜的研制

讨论了不同VA含量不同熔体指数的EVA和各种增粘剂对热熔胶膜耐热性、软化点、剪切强度、拉伸强度、剥离强度等性能的影响。通过采用不同材料试验和配方的筛选，研制出一种90℃剪切强度0．07MPa、拉伸强度0．47MPa、耐热性好、粘接强度高的热熔胶膜，从而拓宽了热熔胶的使用范围。     

Encapsulation of PV modules using ethylene vinyl acetate copolymer as a pottant: A critical review

The primary purpose of this work is to review the literature about what is and is not known about using ethylene vinyl acetate (EVA0 copolymer as the encapsulant (or pottant) material in photovoltaic (PV) modules. Secondary purposes include elucidating the complexity of the encapsulation problem, providing an overview about encapsulation of PV cells and modules, providing a historical overview of the relevant research and development on EVA, summarizing performance losses reported for PV systems deployed since ca. 1981, and summarizing the general problems of polymer stability in a solar environment. We also provide a critical review of aspects of reported work for cases that we believe are important.Failure modes resolved in the early work to establish reliability of deployed modules and the purposes and properties of pottants, are summarized. Typical performance losses in large field-deployed, large-scale systems ranging from 1% to 10% per year are given quantitatively, and qualitative reports of EVA discoloration are summarized with respect to ultraviolet (UV), world-wide location and site dependence.The general stability of polymers and their desirable bulk properties for solar utilization are given. The stabilization formulation for EVA, its effectiveness, and changes in it during degradation are discussed. The degradation mechanisms for the base resin, e.g., unstabilized Elvax 150^TM, and stabilized EVA are indicated for literature dating to the early 1950s, and the role played by unsaturated chromophores is indicated. The limited number of studies relating discoloration and PV cell efficiency are summarized.Observed degradation of EVA or the unstabilized base resin in the laboratory and examples used to measure the degradation are summarized in sections entitled: (1) thermally-induced degradation; (2) photodegradation and photothermal degradation of EVA in different temperature regimes; (3) photobleaching and photodegradation of the UV absorber and cross-linking agent; (4) acetic acid and metal and metal-oxide catalyzed oxidative degradation; and (5) discolaration and PV cell efficiency losses.Processing effects/influences on EVA stability are discussed in sections entitled: (1) EVA raw materials and extruded, uncured films; (2) thermal encapsulation processes; (3) effects of lamination, curing, and curing peroxide on gel content and chromophores formed; and (4) incomplete shielding of curing-generated chromophores. A summary is given for the limited number of accelerated lifetime testing efforts and examples of erroneous service lifetime predictions for EVA are discussed. The known factors that effect the discoloration rate of several EVA formulations are discussed in which the reduction in rate by using UV-absorbing superstrates is a prime example. A summary is given of what is and is not known about EVA degradation mechanisms, degradation from exposures in field-deployed modeules and/or laboratory testing, and factors that contribute to EVA stability or degradation. Finally, conclusions about using Elvax 150 in EVA formulations are summarized, and future prospects for developing the next-generation pottant for encapsulating PV modules are discussed.     

硅烷交联型复合半导电塑料

对于硅烷交联型复合半导电塑料的研究表明，合理的选择EVA，炭黑，交联剂，引发剂，催化剂的种类和适宜的用量，仅仅是提高接枝和凝胶质量分散的必要条件，体系环境的酸碱度才是可以交联的充分条件，只有在体系的环境呈现出中性或弱的碱性时，硅烷才可能与PE和EVA充分接枝和交联。     

EVA共聚物的性能与应用

EVA共聚物广泛用作电线电缆中的热收缩材料,半导电屏蔽材料和阻燃绝缘材料,本文简要综述EVA共聚物的基本性能。     

电子束辐照和氢氧化铝对LLDPE/EVA共混物凝胶含量和力学性能的影响

研究了电子束辐照剂量和氢氧化铝(ATH)的含量对线性低密度聚乙烯(LLDPE)/乙烯-醋酸乙烯酯(EVA)共混物凝胶含量和力学性能的影响。辐照剂量是影响LLDPE/EVA/ATH阻燃体系凝胶含量的主要因素,而ATH对其凝胶含量的影响较小。随着ATH含量的增加,LLDPE/EVA共混物的拉伸强度逐步增加,断裂伸长率迅速下降。所有阻燃体系的拉伸强度均是随着辐照剂量的增加而逐步增大,但辐照剂量对这些阻燃体系的断裂伸长率的影响却比较复杂。     

EPDM/EVA无卤阻燃绝缘材料的开发与应用

主要探讨了在ＥＰＤＭ／ＥＶＡ并用体系中，氢氧化铝、氢氧化镁、硼酸锌和三氧化钼等对无卤阻燃绝缘材料的加工特性和对阻燃、机械性能的影响，并对其加工工艺作了简要介绍。     

Phase morphology and melt viscoelastic properties in blends of ethylene/vinyl acetate copolymer and metallocene-catalysed linear polyethylene

The aim of this study was to determine the linear viscoelastic properties of a series of ethylene/vinyl acetate copolymer/metallocene-catalysed polyethylene (mPEs) blends. Newtonian viscosity showed a pronounced positive deviation from the double reptation model, which assumes miscibility or, at least, cooperative relaxation between the mixed species. Enhanced values of steady-state compliance and elastic indices with respect to those of the pure components were also noted. These features are typical of emulsion-like polymer blends and are thought to arise from additional relaxation processes associated with dispersed phase deformability. Application of the Palierne model for emulsions of two viscoelastic liquids showed good agreement with our experimental dynamic results at both ends of the phase diagram. However, the model failed at intermediate compositions. Through the application of several rheological criteria we were able to locate the phase inversion concentration at a weight fraction of w=0.60 in the mPEs. It is suspected that, in this composition range, a fully co-continuous phase develops due to the phase inversion mechanism, which has considerable effects on the viscoelastic properties of the blends.