环氧大豆油改性水性聚氨酯的制备及性能表征

用二乙醇胺按照不同比例将环氧大豆油中的部分环氧基开环,然后以不同的添加量引入到水性聚氨酯链段中,合成出环氧大豆油改性的水性聚氨酯乳液。通过FT-IR表征及改性前后性能比较,表明部分开环的环氧大豆油是以化学键和的方式接入到聚氨酯分子链段中的。性能测试结果显示:经环氧大豆油改性的乳液的粒径变大,储存稳定性略有下降;改性后胶膜的拉伸强度增加,断裂伸长率下降,耐热性有提高。     

水性环氧耐核辐射涂料的制备

以环氧改性胺乳液为A组分,环氧树脂为B组分,制备了性能优异且环保的水性环氧耐核辐射涂料。研究了环氧改性胺乳液、耐核辐射颜填料及颜料体积浓度(PVC)等因素对涂料性能的影响。结果表明,采用环氧改性芳香胺为固化剂,配合功能性填料钛酸钾晶须制备的水性环氧耐核辐射涂料具有优良耐辐照性能及去污性能,经过8.5×105GY(累积剂量)辐照后漆膜完好,附着力良好。     

水性油墨用环氧改性水性丙烯酸树脂的合成

介绍了一种环氧改性水性丙烯酸树脂的合成方法,并由改性树脂配制了水性凹版塑料油墨.讨论了亲水单体含量对树脂水溶性的影响和引入环氧丙烯酸酯含量对油墨附着牢度、复合牢度的影响,并经红外表征证明达到了环氧改性水性丙烯酸树脂的目的.实验表明,由环氧改性水性丙烯酸树脂配制的水性油墨,其性能技术指标达到或优于国家标准和实际应用要求,在凹版塑料油墨领域具有很大的应用价值和广阔的市场前景.     

有机硅嵌段改性聚氨酯/环氧树脂互穿网络聚合物的研究

以甲苯-2,4-二异氰酸酯(TDI)、聚醚二元醇为主要原料制得-NCO封端的预聚体,并按一定比例和环氧树脂E-51混匀;另外合成一系列分子量不同的氨基聚硅氧烷(AG),并利用多元胺类作固化荆,合成一系列氨基聚硅氧烷改性的聚氨酯／环氧互穿网络聚合物。测试了材料的力学性能、表面接触角、吸水率,同时对材料进行了红外光谱和表面电子能谱(ESCA)分析。结果表明,氨基聚硅氧烷／聚氨酯／环氧互穿网络聚合物是一种具有良好疏水性能的新型低表面能材料,同时其力学性能的变化与氨基聚硅氧烷的含量以及分子量的大小等密切相关。     

改性聚硅氧烷/纳米SiO2杂化膜的制备与疏水性

先以甲基丙烯酸十八醇酯(SMA)、烯丙基缩水甘油醚(AGE)和含氢硅油(PHMS)的硅氢加成反应制得一种梳状结构的十八酯基/环氧基改性聚硅氧烷(PSAMS),再通过其与氨基功能改性纳米SiO2间的接枝共聚反应制备了一种改性聚硅氧烷/纳米SiO2杂化材料(PSAMS-SiO2).采用一次浸渍法,简便地在天然棉纤维表面制得...     

一种透明环氧改性有机硅树脂的制备与性能

采用二甲基二乙氧基硅烷与γ-(2,3-环氧丙氧)丙基三甲氧基硅烷为原料,经溶胶凝胶法,制备了透明的环氧改性有机硅树脂预聚物。将所得环氧改性有机硅树脂预聚物在4-甲基六氢苯酐为固化剂,二甲基苄胺为促进剂,经80℃固化1 h,120℃固化1 h,150℃固化2 h后,获得透明的环氧改性有机硅树脂固化物。研究了固化物的性能,结果表明,随着R/Si值增大,所得透明环氧树脂的透光率逐渐升高,但其硬度、玻璃化转变温度和热分解温度都逐渐降低。总体而言,当环氧改性有机硅树脂R/Si=1.6时,固化物具有很高的透光率,较好的热稳定性,可调的硬度,对基材有良好的粘接力,这表明所得环氧改性有机硅树脂有望用于光学透明器件的封装。     

硅藻土负载环氧改性沥青的制备及其与TAF环氧改性沥青性能的对比

选用双酚A型环氧树脂E44和一种多胺类固化剂对基质沥青进行改性:以硅藻土为载体,负载环氧树脂E44后与沥青、固化剂混合,制备出硅藻土负载环氧改性沥青.对比了硅藻土负载环氧改性沥青和日本TAF环氧改性沥青的流变性能、低温性能、微观结构及经济成本,结果表明硅藻土负载环氧改性沥青具有优异的相容性和高温性能,低温抗裂性能相对较...     

高固体分环氧海洋防腐蚀涂料的研究进展

海洋环境中,钢结构的腐蚀不可避免,有机涂层是一种延缓金属腐蚀的最有效、最经济的材料之一。其中高固体分环氧涂料由于绿色环保、涂层致密性好、可厚涂等特点在海洋重防腐中得到广泛的应用。对目前高固体分环氧厚膜、超厚膜涂料的研究进展,存在的问题及解决方法进行了详细的介绍。其中,环氧树脂、胺类固化剂作为环氧涂料中的主要的成膜物质,对涂层的性能起着关键的作用。总结了几种在高固体分环氧涂料中切实可行的环氧树脂增韧改性方法,同时指出开发耐冲击性能优异,耐高温,低温固化、水下固化的环氧固化剂也是环氧固化剂的发展趋势。通过曼尼希碱改性合成的环氧固化剂,恰好能满足各种性能的要求,阐述了该类环氧固化剂的合成研究进展状况。     

改性氨基硅油的合成及应用研究

以端侧氢硅油与丙烯酸甘油酯为原料,通过硅氢加成反应,得到的环氧硅油中间体,再与叔氨基化合物进行开环反应,合成了氨基封端聚硅氧烷。探讨了不同反应条件对改性硅油性能的影响,确定了最佳反应条件:以低含氢硅油与丙烯酸甘油酯为原料,铂催化剂用量为单体质量的0.02%,反应温度为120℃下反应4h,生成的环氧硅油(中间体Ⅰ)在丙二醇溶液中与三甲胺盐酸盐,85~90℃氨化反应2h,得到改性氨基硅油。制备的硅油乳液具有亲水性,应用于织物的结果表明:整理后的织物具有低黄变性和良好的柔软度。     

环氧聚硅氧烷丙烯酸酯的合成及其光固化的研究

本文以环氧聚硅氧烷〈简称ＥＰＳ〉与丙烯酸进行加成反应，合成了一种游离基光固化的有机硅预聚物－－环氧聚硅氧烷丙烯酸酯〈简称ＡＥＰＳ〉。该予聚物既具有热固性硅橡胶的特性，又具备丙烯酸酯树脂快速光固化的优点，是一种比较理想的光敏聚合材料。它已在新发展的ＵＶ－固化光纤涂料中应用。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.