固体有机硅消泡剂

本文介绍了以聚二甲基硅氧烷为活性组分加载体和助剂制备固体有机硅消泡剂的方法及其应用。     

有机硅消泡剂的应用进展

介绍了有机硅消泡剂的分类及基本成分,阐述了有机硅消泡剂的消泡抑泡原理及其特点,概述了有机硅消泡剂在纺织、造纸、涂料等领域的应用情况,并展望了有机硅消泡剂的发展方向。     

有机硅消泡剂

综述了有机硅消泡剂在织物整理方面的应用情况。论述了有机硅消泡剂的发展与现状,探讨了有机硅消泡剂的消泡机理,介绍了有机硅消泡剂的性能,并对3种消泡剂的性能进行了对比。     

有机硅消泡剂与造纸

阐述了有机硅消泡剂的消泡原理及种类,简介造纸工业中常用的有机硅消泡剂的制备方法。     

缔合增稠剂

乳胶漆是聚合物和颜料颗粒在水性介质中的分散体。分散体的粘度在分散相总体积为50％以下时,几乎就是介质的粘度,所以不增稠乳胶漆的连续相(水相)是无法施工的。 目前作为乳胶漆的增稠剂大多为水溶的纤维素醚。用它增稠的乳胶漆的流变性如图一所示,从图中可见到,在受到剪切后,粘度迅速下降。为了顾及乳胶漆的“干遮盖力”要求,必须有足够的湿膜厚度,这就需要在高剪切速率下有足够高的粘度,这就得增加纤维素醚的用量或改     

有机硅消泡剂的制备与应用

有机硅消泡剂作为应用最广泛的一类消泡剂产品,以其独特的优异性能,日益为人们所关注,在国民经济的各个领域中需要量越来越大。有机硅消泡剂在化学结构上,同其它有机系消泡剂不同,近似非极性,与水或有极性原子团的物质不发生缔合;与烃及分子中有烃基的物质不缔合;亦不同起泡物     

有机硅乳液消泡剂的研制

本文叙述了以甲基硅油为主要原料,加增稠剂和分散剂,采用非离子型乳化剂在水相中乳化,制备JSE-1高效有机硅乳液消泡剂的方法。讨论了硅油、二氧化硅填料、乳化剂、增稠剂以及加料顺序、乳化方法等对乳液稳定性和消泡效果的影响。     

高效有机硅消泡剂的制备

针对气田钻井液发泡问题,从钻井液发泡原因和消泡机理出发,在综合考察现今国内外各种消泡体系的基础之上,研制了一种以有机硅为主体的乳液型消泡剂LS。通过L16正交实验确定了影响消泡剂LS产品性能的条件,得出各因素对反应的影响次序为:有机硅质量分数>乳化温度>乳化剂质量分数>乳化时间;优化的合成条件为:有机硅质量分数15%,乳化剂质量分数5%,乳化温度80℃,乳化时间20 m in。通过性能评价实验,证明该消泡剂具有用量少(质量分数为0.2%)、消泡效果好(密度恢复率为98.96%)、抑泡能力强(抑泡密度恢复率为99.13%)、无毒无污染等优点,作为一种高效环保型的钻井液消泡剂,具有广阔的发展应用前景。LS已工业化生产,现场应用效果良好。     

Speeding up alumina grinding with silicone additives

Conclusions Adding 0.05% (by weight of alumina) silicone liquid GKZh-94 to commercial raw and calcined alumina before grinding reduces the grinding time in a vibromill by a factor of 4–5, and in a ball mill by a factor of 6.Acceleration of the dry grinding under the influence of this silicone occurs owing to the adsorption of the silicone in the hydrophobization of the powder. As a result, sticking of the fine grains of powder to the surface of the large grains, balls, and walls of the mill does not occur.Translated from Ogneupory, No. 8, pp. 1–4, August, 1968.     

Antimicrobial silicone rubbers based on photocatalytically active additives

The modification of plastics to generate germ-reducing surface materials is a promising strategy to decrease nosocomial infections in hygiene-sensitive areas. In this paper, photocatalytically active nanoparticles were incorporated as additives, not as a coating, into silicone rubber matrix material to produce elastic antibacterial bulk materials. Samples with 5 wt% and 10 wt% of two different types of TiO₂ and ZnO were prepared and investigated. The thermal analysis of the developed materials showed a complete vulcanization of the developed materials and slight modifications of mechanical properties were found. Investigations of the surface of the materials indicated no changes in the wettability of the surfaces or in their fourier transform infrared spectrometer (FT-IR) spectra, suggesting no degradation of the developed material. The photocatalytic activity on the surface of the test samples was investigated by microbial tests with Escherichia coli, Pseudomonas fluorescens, and Staphylococcus aureus bacteria. Depending on the additive type and the test germs, the samples showed different intensities of a germ-reducing effect (up to >99,999%).     

消泡剂的分类与应用技术

本文详细介绍了消泡剂的作用原理、分类和在工业领域内的应用技术等情况。     

Controlled drug release in silicone adhesive utilizing particulate additives

Polydimethylsiloxane (PDMS) based adhesives were prepared by cross-linking tetraethoxyorthosilicate (TEOS) while controlling stoichiometry with PDMS, acid catalyst, and water. Particulate additives, alginate and bentonite, were added during the cross-linking process. Cationic drug lidocaine was incorporated into the adhesive with or without additive, and the time-dependent drug release profile was evaluated in phosphate buffered saline and ethanol, respectively. According to kinetic fitting to power function and parabolic diffusion, both solvent and additive type influenced drug release. In particular, particulate additives were found to suppress or facilitate drug release in water or ethanol, respectively.     

二甲胺聚醚改性有机硅表面活性剂的合成

以不饱和的聚醚和环氧氯丙烷为原料，合成出环氧不饱和聚醚；再与低含氢硅油进行硅氢加成反应，合成出环氧聚醚改性聚甲基硅氧烷；接着用二甲胺对环氧基开环，得到二甲胺聚醚改性有机硅表面活性剂。研究了硅氢加成反应条件对含氢硅油转化率的影响、用IR谱图表征了关键中间体及产物的结构、测定了产物的表面特性。硅氢加成反应的最佳工艺为：反应温度75℃、反应时间5h、聚醚中的C=C键与含氢硅油中的Si-H基的量之比为1．1：1．0；二甲胺聚醚改性有机硅表面活性荆的表面张力为21．4mN／m，在农纷螟施净水溶液中的临界胶束质量分数为3％，在临界胶束浓度下螟施净水溶液的表面张力值为24．8mN／m，能大幅降低农药的表面张力（降幅这24％）；从亲水亲油平衡（HLB）值看，二甲胺聚醚改性有机硅表面活性荆的亲油性稍强于亲水性，且HLB值在一定范围内随着pH值的降低而提高。     

Rhodia launches flame retardant compounds

Flame retardant polyamide (PA) compounds based on environmentally-friendly technology have been launched by Rhodia Engineering Plastics for the electrical and electronic industry.This is a short news story only. Visit www.addcomp.com for the latest additives and compounding industry news     

Mobility and distribution of silicone additives in coatings; a spectroscopic study

The concentration of four prepared silicone/poly(ether) additives at the film-air (F-A) and film-substrate (F-S) interfaces of films prepared on glass and poly(ethylene) substrates is characterized via quantitative attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectroscopy. Three different coating systems, an acrylic/melamine solvent based system, an acrylic/isocyanate solvent based system, and an aqueous poly(urethane) suspension, were examined. It is found that the nature of the substrate, the mechanism of film formation, and the inherent coating/additive compatibility are all factors which may significantly influence additive behavior. Also the acrylic/melamine system generally reveals a slight degree of enrichment of both additive components to the F-A interface, but the acrylic/isocyanate system exhibits a more pronounced concentration gradient due to a lesser degree of compatibility. In contrast, the water-based poly(urethane) exhibits a more complex behavior, with the poly(ether) component revealing significant enrichment to the F-A interface, and the siloxane component exhibiting a decreased concentration as the interface is approached. Here, the mechanism of film formation involves a water flux passing out of the film which may serve to transport the water soluble poly(ether) components to the F-A interface. At the F-S interface, it is demonstrated that the nature of the substrate may influence additive behavior, and it is found that the concentration of the more polar poly(ether) components generally exhibits a lesser degree of enrichment to a poly(ethylene) substrate, relative to glass.     

Diffusion of adhesion promoting and crosslinking additives in an uncured silicone sealant

A method has been devised for measuring the diffusion coefficient D of additives that act as adhesion promoters and crosslinking agents in uncured silicone sealants. This has been used to measure D for tetra-t-butyltitanate (TBT) and isobutyltrimethoxysilane (BTMS) in a sealant at 25°C. The value of D for TBT was found to be constant but that for BTMS decreased with the duration of the experiment, possibly due to the interaction of the silane with the silica particles.     

Rhodia,ECNU and Others Signs to Strengthen Green Chemistry

<正> Rhodia announced on August 31st that the specialty chemicalproducer,the French National Center for Scientific Research(CNRS),the Ecole Normale Superieure of Lyon (ENSL) and the East China Normal University (ECNU) of Shanghai have signed aMemorandum of Understanding to strengthen their scientific col-