JH—3橡胶型压敏胶的研究

介绍了以天然橡胶和丁苯橡胶为主材料，以烃类树脂为增粘剂压敏胶的制备，并研究了丁苯橡胶、树脂、填料及其它助剂对压敏胶性能的影响。     

橡胶型压敏胶粘剂的研制

本文介绍了以天然橡胶、丁苯橡胶和α-萜烯树脂为主体材料制备压敏胶的工艺过程,及对影响性能的一些因素进行了分析讨论。     

橡胶型压敏胶的研制

压敏胶就是对压力敏感的胶粘剂。性能妈的压敏胶必须具有好的初粘力(快粘力)、剥离力(粘合力)和持粘力(内聚力),且必须是内聚力>粘合力>初粘力。三大粘合性能之间存在一定的依赖关系,例如通常提高内聚力的方式都会降低初粘力,反之亦然。因此,在达到三项性能平衡的同时,各项指标越好则胶的性能越好。橡胶型压敏胶通常由橡胶、增粘树脂、软化剂、防老剂、溶剂等组成。其中,橡胶是主体部分,它赋予胶粘     

橡胶型压敏胶的研究进展

由于橡胶型压敏胶(RPSAs)成本和性能上的优势,近年来其研发和应用领域越来越广。天然橡胶和合成橡胶作为橡胶压敏胶的主粘料因含有双键和易混容因而易于改性。增粘剂和填料的研发是改性研究的重点。综述了RPSAs主粘料、增粘剂和填料的研究进展,对未来发展和改性的趋势进行了预测。     

橡胶型压敏胶的研究进展

橡胶型压敏胶(RPSAs)广泛应用于胶带、标签等领域,其粘合性能评价标准有初粘性、剥离强度和持粘性3项。用作RPSAs基体的橡胶弹性体主要有天然橡胶(NR)、合成橡胶(SR)和热塑性弹性体(TPE)3类,新型TPE基RPSAs为近年来的研究热点。对于RPSAs的优化主要从基体改性和优化配方两个方面展开,基体改性采用物理和化学改性手段,配方优化包括调整增粘树脂品种和用量等。与其他种类的压敏胶相比,橡胶型压敏胶具有独特优势,应用领域越来越广。     

SDS型热熔压敏胶的研制

以ＳＩＳ,ＳＢＳ为主体原料,配合增粘树脂,软化剂,防老剂等研制出ＳＤＳ型热熔压敏胶,讨论了各组分对性能的影响,确定了合理的配方和工艺,在制备方法上也有新的改进。     

环境友好型丙烯酸酯压敏胶研究进展

介绍了丙烯酸酯乳液型PSA(压敏胶)的合成原理和黏附特性。综述了乳液型、热熔型和无溶剂型等几种丙烯酸酯类PSA的性质、作用和研究进展,并对其今后的发展趋势进行了展望。     

热塑性弹性体型热熔压敏胶的研究进展

介绍了热熔压敏胶用热塑性弹性体以及增粘树脂的特点、作用以及研究进展,并对热熔压敏胶的发展方向以及应用前景进行了展望。     

树脂型压敏胶的研究进展

对近年来出现的各种类型树脂型压敏胶进行了分类,综述了各类压敏胶的优缺点及改性方法。展望了树脂型压敏胶的应用前景和发展方向。     

溶剂型橡胶系压敏胶的研究

采用自交联工艺合成溶剂型橡胶系压敏胶,讨论了增粘树脂的用量、软化剂的用量、交联剂的用量、聚合反应温度、烘胶温度和烘胶时间对压敏胶性能的影响。实验表明,增粘树脂可以有效地提高压敏胶的初粘性和剥离强度,交联剂能够全面调节压敏胶的性能,适当的烘烤温度和烘烤时间有利于提高压敏胶的粘接性能。得出了最佳工艺条件为:增粘树脂与天然橡胶的质量比为701∶00,软化剂含量为20%,交联剂为0.4%,接枝共聚的温度为80℃。     

一种固化型压敏胶的研制

本文研制出一种固化型聚氨酯预聚体接技改性丙烯酸酯压敏胶。阐述了该胶的制备原理、固化机理、制备方法、固化前后的性能。     

橡胶系压敏胶粘剂

本文就橡胶系压敏胶粘剂主要组分的作用和选择依据及其相关影响等方面作了介绍。     

Rheology and Adherence of Pressure-Sensitive Adhesives

We have studied the relationship between rheological and peeling properties for hot-melt pressure-sensitive adhesives based on homopolymers or copolymers blended with tackifying resins. In this article, we particularly try to demonstrate that it is possible to define a quantitative link between rheology and adherence when the model formulations are deposited on substrates with strong (thermodynamic) adhesion. We describe the experimental results obtained on these model formulations and discuss the quantitative relationships obtained. In the case of “adhesion modulation” (derived from different treatments of the substrates), we show that the relationships become much more complicated, even with the same model adhesives. At the end, we discuss on the competition between adhesion and dissipation in the case of poor adhesion.     

Curable Optically Clear Pressure-Sensitive Adhesives

A prototype transfer label construction that includes (a) an optically clear curable pressure-sensitive adhesive layer, (b) a curable epoxy layer, and (c) a transparent carrier layer has been developed. This transfer label construction is particularly useful for protective coatings in color filters for use in a liquid-crystal display panel structure. The curable epoxy and the curable pressure-sensitive adhesive (PSA) are applied to the color filter and then exposed to ultra violet (UV) radiation. The radiation transforms the PSA from a removable adhesive to a permanent adhesive. The color filter with the UV-cured adhesive is then baked to fully cure the adhesive layer, which further transforms the adhesive into an ultra-high-adhesion laminating adhesive. Such progressive transformation to different types of adhesive is monitored and confirmed by the shift in viscoelastic window.     

Rheological Study on Tack of Pressure-Sensitive Adhesives

It is pointed out that the tack of pressure-sensitive adhesives should be expressed in terms of rolling friction coefficient f of the adhesives. Values of f were determined by both rolling ball and pulling cylinder experiments, and the dependence of f upon viscoelastic properties and thickness of the adhesives was studied. The experimental results were interpreted by the model theory previously proposed. It is also shown that the tack of pressure-sensitive adhesives by the conventional ball tack tests corresponds to f measured at the velocity ranging from v ～ 10 to v ～ 10² cm/sec.     

Rheological Study on Tack of Pressure-Sensitive Adhesives

It is pointed out that the tack of pressure-sensitive adhesives should be expressed in terms of rolling friction coefficient f of the adhesives. Values of f were determined by both rolling ball and pulling cylinder experiments, and the dependence of f upon viscoelastic properties and thickness of the adhesives was studied. The experimental results were interpreted by the model theory previously proposed. It is also shown that the tack of pressure-sensitive adhesives by the conventional ball tack tests corresponds to f measured at the velocity ranging from v ∼ 10 to v ∼ 10² cm/sec.     

Effect of Coumarone-Indene Resin on Adhesion Property of SMR 20-Based Pressure-Sensitive Adhesives

The viscosity, tack, and peel strength of a natural rubber (SMR 20)–based pressure-sensitive adhesive (PSA) was studied using coumarone-indene resin as the tackifier. The resin loading was varied from 0–80 parts per hundred parts of rubber (phr). Toluene was used as the solvent throughout the experiment. The viscosity of PSA was measured using a Haake Rotary Viscometer whereas loop tack and peel strength were determined using a Lloyd Adhesion Tester. PSA was coated onto the substrates using a SHEEN hand coater to give a coating thickness of 60 μm and 120 μm. Results show that the viscosity and tack of the adhesive increases with resin content due to the concentration effect of tackifier resin. However, for the peel strength, it increases up to 40 phr of resin for both coating thickness, an observation that is attributed to the wettability of substrates.     

用悬浮聚合法制造再剥离性压敏胶的研究

利用悬浮聚合工艺制备压敏胶是一种新颖的方法。本文以丙烯酸酯类为主要单体，经悬浮聚合，制成了一种重复粘贴性能良好的压敏胶，并对聚合过程及影响产品性能的主要因素进行了探讨。     

Understanding Cracking Versus Cavitation in Pressure-Sensitive Adhesives: The Role of Kinetics

We perform probe-tack experiments on highly viscous silicone oils. Direct observation during the experiment shows the existence of several mechanisms for releasing the stress. Beyond bubble nucleation and instantaneous growth (reported in a previous work), delayed bubble growth is observed at higher traction velocities. At even higher velocities, cracks at the interface between the plate and the liquid appear before the bubbles have grown to their full size. Bubbles and cracks are thus observed concomitantly. At much higher velocities, cracks develop fully before the bubbles can be seen. We present a theoretical model that describes these regimes, using a Maxwell fluid as a model for the actual fluid. The predictions for the force peak are in qualitative agreement with the data. We discuss to what extent a Maxwell model is adapted to this situation. In particular, we discuss the threshold value for cavitation or cracking in the case of a purely elastic material and obtain a complementary, tentative interpretation of Dahlquist's criterion for stickiness.     

Effect of In Situ Polymerization of Styrene onto Natural Rubber on Adhesion Properties of Styrene-Natural Rubber (SNR) Adhesives

Styrene-based deproteinized natural rubber (SNR) latex was synthesized by in situ polymerization. Three pre-vulcanization systems [conventional-cured (CV), semi-efficient-cured (Semi-EV), and efficient-cured (EV)] were studied in terms of tensile and adhesion properties. Good tensile properties were observed for CV and EV SNR. The Semi-EV SNR showed the best adhesion properties based on the good anchorage performance in all substrate pairings (polystyrene–polystyrene, polystyrene–rubber, and rubber–rubber). The pH modification on SNR latex via KOH addition has beneficial effects of removing protein layers, resulting in more styrene grafting sites in the rubber molecules. Consequently, the tensile and adhesion properties of the SNR are improved as more styrene polymers are grafted onto the rubber matrix. Semi-EV SNR with pH 12 has superior adhesive performance; hence, it is suitable for use as a pressure-sensitive adhesive.