有机硅压敏胶（二）

介绍了提高有机硅压敏胶黏附性的方法,有机硅压敏胶中所用的改性助剂;有机硅压敏胶的品种系列（过氧化物硫化、加成型）。有机硅压敏胶所涉及的相关材料（背材及底涂剂、背面处理剂）;过氧化物硫化型有机硅压敏胶的配制（高固体质量分数、低黏度品种,采用甲基苯基硅橡胶生胶与MQ硅树脂为原料配制,耐300℃高温品种）;加成型有机硅压敏胶的配制（耐高温品种,高固体质量分数、低黏度品种）。     

有机硅压敏胶的研究进展

综述了国内外有机硅压敏胶的研究开发现状，着重分析了溶剂型、高固含量型、辐射固化型、热溶型、树脂改性型及其它类型有机硅压敏胶的特点和组成与性能的关系，并对有机硅压敏胶的发展趋势作了展望。     

有机硅压敏胶的应用研究进展

在总结有机硅压敏胶组成及合成反应的基础上,概述了溶剂型、乳液型、热熔型及无溶剂有机硅压敏胶的制备方法.根据有机硅压敏胶的性能特点总结了相关应用,并对其今后的发展方向和前景进行了展望.     

有机硅压敏胶（二）

介绍了提高有机硅压敏胶黏附性的方法,有机硅压敏胶中所用的改性助剂;有机硅压敏胶的品种系列(过氧化物硫化、加成型).有机硅压敏胶所涉及的相关材料(背材及底涂剂、背面处理剂);过氧化物硫化型有机硅压敏胶的配制(高固体质量分数、低黏度品种,采用甲基苯基硅橡胶生胶与MQ硅树脂为原料配制,耐300℃高温品种);加成型有机硅压敏胶的配制(耐高温品种,高固体质量分数、低黏度品种).     

压敏胶的研究进展

综述了压敏胶研究进展,包括橡胶型压敏胶、热塑性弹性体类压敏胶、丙烯酸酯类压敏胶、有机硅类压敏胶及聚氨酯类压敏胶,并展望了压敏胶的发展趋势。     

有机硅压敏胶的研究进展

综述了国内外有机硅压敏胶的研究开发现状,着重分析了溶剂型、高固含量型、非芳香族溶剂型和无溶剂型有机硅压敏胶的特点和组成与性能的关系,并对有机硅的应用前景作了展望。     

压敏胶黏剂研究进展

综述了几类压敏胶黏剂(包括橡胶型压敏胶、热塑弹性体型压敏胶、丙烯酸酯型压敏胶、有机硅型压敏胶及聚氨酯型压敏胶等)的结构、性能特点及其研究现状,并指出采用本体法的UV-LED引发、交联的压敏胶黏剂是一种节能、环保型压敏胶,也是今后的发展方向。     

有机硅压敏胶(一)

介绍了有机硅压敏胶的特性、分类、组成、结构、硫化特性,有机硅压敏胶的黏附性及评价方法,以及改善有机硅压敏胶黏附性的方法.     

研发动态

正道康宁推出有机硅离型剂和PSA产品5月24~26日,道康宁参加了在上海国家会展中心举行的第十三届上海国际胶粘带、保护膜和光学膜展览会(APFE 2017),重点展出了应用于高性能离型膜和保护膜的先进有机硅离型剂和有机硅压敏胶(PSA)产品组合。道康宁表示其有机硅离型剂和有机硅压敏胶(PSA)可降低涂布成本、避免VOCs排放、提高光学透明度,并能在较低温度下快速硫化。     

道康宁为压敏胶工业提供创新解决方案

<正>在上海举行的第五届国际胶粘带、保护膜及光学膜展览会上,道康宁公司携性能可靠的有机硅压敏胶和离型剂解决方案亮相。道康宁展出了其为亚洲高端电子和汽车产品市场开发的高性能有机硅压敏胶产品,并着重介绍了有机硅压     

有机硅压敏胶的研制

采用价格低廉的水玻璃制备MQ硅树脂,通过对硅树脂体系引入苯基、乙烯基提高压敏胶的综合性能,研究MQ硅树脂的合成与压敏胶的制造工艺,制备出高性能的有机硅压敏胶。     

纳米SiO2-Al2O3协同改性有机硅压敏胶的性能研究

采用纳米SiO2和Al2O3两种粉体协同对有机硅压敏胶进行改性,并以改性后的压敏胶为胶黏剂,聚酰亚胺薄膜、云母纸、无碱玻璃布为基材制备柔软复合材料。研究了纳米粒子含量和比例对有机硅压敏胶耐热性和柔软复合材料电性能的影响。实验结果表明:适量的纳米SiO2和Al2O3加到有机硅压敏胶中,使压敏胶的表观分解温度和复合材料的击穿场强得到明显提高。     

Stress Relaxation During Bond Formation and Adhesion of Pressure-Sensitive Adhesives

Relaxation properties and adhesion of pressure-sensitive adhesives (PSAs) have been studied with the Probe Tack method under the conditions corresponding to the adhesive bond formation. Typical representatives of various PSA classes are examined: adhesives based on the styrene-isoprene-styrene (SIS) block copolymer, polyisobutylene of two molecular weights, acrylic and silicone PSAs. By comparison of the adhesive and relaxation behaviors of different PSAs it has been established that the PSA relaxation contributes appreciably to the strength of the adhesive bond and underlies the impact of contact time on adhesion. Direct correlation has been established between the compressive stress relaxation in the course of bond formation and the mechanism of debonding. All the examined PSAs can be classified into two groups: 1) the fluid-like PSAs that are capable of relaxing fully under compression (PIB, silicone adhesives) and 2) the PSAs, which reveal a residual unrelaxed stress. Physically crosslinked SIS and chemically crosslinked acrylic adhesives exemplify the PSAs of the second group. The occurrence of two peaks on the debonding stress–strain curves is typical of the PSAs of the second group. High adhesive strength requires the contribution of the longer relaxation times that vary for different PSAs in the range from 150 to 800 s. Minimum values of the longer relaxation times are featured for fluid adhesives, whereas the maximum values are found for crosslinked, network, and entangled adhesives. The adhesive strength achieves its maximum when the slow relaxation processes become dominating. Relative contributions of viscous and elastic deformations to relaxation properties of PSAs are assessed in terms of the Deborah number.     

Stress Relaxation During Bond Formation and Adhesion of Pressure-Sensitive Adhesives

Relaxation properties and adhesion of pressure-sensitive adhesives (PSAs) have been studied with the Probe Tack method under the conditions corresponding to the adhesive bond formation. Typical representatives of various PSA classes are examined: adhesives based on the styrene-isoprene-styrene (SIS) block copolymer, polyisobutylene of two molecular weights, acrylic and silicone PSAs. By comparison of the adhesive and relaxation behaviors of different PSAs it has been established that the PSA relaxation contributes appreciably to the strength of the adhesive bond and underlies the impact of contact time on adhesion. Direct correlation has been established between the compressive stress relaxation in the course of bond formation and the mechanism of debonding. All the examined PSAs can be classified into two groups: 1) the fluid-like PSAs that are capable of relaxing fully under compression (PIB, silicone adhesives) and 2) the PSAs, which reveal a residual unrelaxed stress. Physically crosslinked SIS and chemically crosslinked acrylic adhesives exemplify the PSAs of the second group. The occurrence of two peaks on the debonding stress-strain curves is typical of the PSAs of the second group. High adhesive strength requires the contribution of the longer relaxation times that vary for different PSAs in the range from 150 to 800 s. Minimum values of the longer relaxation times are featured for fluid adhesives, whereas the maximum values are found for crosslinked, network, and entangled adhesives. The adhesive strength achieves its maximum when the slow relaxation processes become dominating. Relative contributions of viscous and elastic deformations to relaxation properties of PSAs are assessed in terms of the Deborah number.     

压敏胶在药物透皮递释系统中的应用

压敏胶是药物透皮递释系统（TDDS）的基本组成之一，它能保证TDDS与皮肤紧密接触，使药物的皮肤渗透按设计的速率进行。文中介绍压敏胶在TDDS中的作用与要求、几种常用压敏胶（如聚异丁烯型．丙烯酸型、硅酮型等）及其应用。     

Silicone pressure-sensitive adhesives with selective adhesion characteristics

The peel, probe tack, and loop tack adhesion characteristics of peroxide-cured silicone pressure-sensitive adhesives (PSAs) are investigated with respect to adhesive composition, peroxide concentration, and type of substrate. These adhesion properties decrease with increasing benzoyl peroxide concentration and their adhesion values vary noticeably with the substrate type. However, the loop adhesion to 'difficult-to-wet' surfaces (e.g. silicone-coated substrates) can be selectively enhanced by incorporating an organofunctional silicone into the silicone PSA mixture. The enhancement in adhesion is attributed to a wetting/adhesion improvement at the adhesive- substrate interface, and relates to the type of organosilicone modifier in the order aminosilicone > vinylsilicone > epoxysilicone > fluorosilicone.     

Properties of UV-curable solvent-free pressure sensitive adhesive

In this study, the effects of methyl methacrylate (MMA), trimethylolpropane triacrylate (TMPTA), difunctional silicone urethane acrylate oligomer, and UV-dose on the adhesive properties of UV-curable pressure-sensitive adhesives (PSAs) were investigated, for further optimizing the adhesive properties to meet the requirements on high holding power and low peel strength. The results illustrated that increasing the MMA content decreased the peel strength and improved the holding power. The variation of TMPTA content from 1 to 10 wt% significantly enhanced the holding power from 1?h to above 120?h. The gel fraction increased with increasing TMPTA content. This increment was caused by the cross-linking of TMPTA after UV exposure. The peel strength of UV-curable PSAs was reduced to zero when oligomer content was more than 40 wt%, whereas the holding power was significantly enhanced from 5?h to above 120?h as the oligomer content increased up to 70 wt%. When the UV-dose increased, the peel strength decreased and the holding power increased. Therefore, UV-curable PSAs with very low peel strength and high holding power above 120?h were successfully synthesized and they possessed desirable features which could be fabricated to meet the specific requirements for industrial applications.     

Molecular weight and crosslinking on the adhesion performance and flexibility of acrylic PSAs

Acrylic pressure sensitive adhesives (PSAs) are used in the production of flexible displays. Acrylic PSAs must have high flexibility and recovery to meet the industry demands for flexible displays. For these reasons, acrylic PSAs were designed to determine the effects of molecular weight and cross-linking on acrylic PSAs. Stress relaxation and creep tests were measured with dynamic mechanical analysis to identify the flexibility and recovery of the acrylic PSAs. The molecular weight and glass transition temperature of the PSAs were measured by gel permeation chromatography and differential scanning calorimetry. A texture analyzer was used to measure the adhesion performance of the acrylic PSAs. With increasing molecular weight, the adhesion performance increased, especially from 86 to 108 K molecular weight PSAs. This is due to the entanglement of the polymer chains. The stress and recovery of cross-linked acrylic PSAs was much higher than that of neat acrylic PSAs. This result is attributed to interactions between the polymer chains due to cross-linking.     

Novel pyridinium photoinitiators and their applications for the ultraviolet crosslinking of acrylic pressure‐sensitive adhesives

The demand for ultraviolet (UV)‐crosslinkable pressure‐sensitive adhesives (PSAs) has rapidly been increasing. A variety of different PSAs containing new photoreactive pyridinium derivatives have been evaluated for their effectiveness in improving adhesion and cohesion in UV‐crosslinkable PSAs. PSAs have been evaluated with respect to the tack, peel adhesion, and shear strength. This article summarizes the breakthrough technology used to achieve better performances in UV‐crosslinkable acrylic PSAs. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007