80℃固化高剥离环氧树脂胶粘剂

介绍了一种８０℃固化高剥离环氧树脂胶粘剂,用于金属,非金属粘接,具有较高的剪切及剥离强度和综合性能。     

40℃固化高强度高剥离耐热环氧树脂胶粘剂

介绍了一种８０℃固化，耐热１３０℃结构胶粘剂，该胶具有良好的综合性能。     

PEEL ADHESION PROPERTIES OF AIR-DRIED PHARMACEUTICAL PRESSURE SENSITIVE ADHESIVE

ABSTRACT

The performance of a pharmaceutical pressure sensitive adhesive, whose liquid formulation is based on a multicomponent mixture of solvents, has been examined during two peel adhesion types of tests (90° dynamic adhesive strength peel test and 180° release liner peel test). The experiments were carried out under various drying temperatures, initial coating thickness, and types of backing film and release liner. The results show that the peel force depends mainly on the dry film weight of the tested adhesive. The type of the backing film which is used to form the adhesive also affects its peel adhesion properties.     

影响Nomex蜂窝节点强度因素的研究

对影响Nomex蜂窝节点强度的因素进行了研究,其中蜂窝制造工艺途径、芯条胶的型号及粘度对蜂窝节点强度具有显著的影响。结果表明：通过优化工艺途径、选择合适型号的芯条胶及将芯条胶的粘度调配至适当范围,有利于提高蜂窝的节点强度。     

Adhesion behavior of natural rubber‐based adhesives crosslinked by benzoyl peroxide

The loop tack, peel, and shear strength of crosslinked natural rubber adhesive were studied using coumarone‐indene and toluene as the tackifying resin and solvent, respectively. The concentration of benzoyl peroxide‐the crosslinking agent—was varied from 1 to 4 parts per hundred parts of rubber (phr). A SHEEN hand coater was used to coat the adhesive on the polyethylene terephthalate substrate at various coating thickness. Loop tack, peel, and shear strength were measured by a Llyod adhesion tester operating at 30 cm min^?1. Result shows that loop tack and peel strength of the adhesive increases up to 2 phr of benzoyl peroxide concentration after which it decreases with further benzoyl peroxide content. This observation is attributed to the optimum crosslinking of natural rubber where optimum cohesive and adhesive strength occurs at 2 phr peroxide loading. However, for the shear strength, it increases with increasing benzoyl peroxide concentration where higher rate of increase is observed after 2 phr of peroxide content, an observation which is associated to the steady increase in cohesive strength of crosslinked rubber. In all cases, the adhesion properties of adhesives increase with increase in coating thickness. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

用废EPS制备低毒清香型胶粘剂

以橙皮为原料提取精油并对其作GC分析,以精油、乙酸乙酯及丙酮作混合溶剂,用废聚苯乙烯泡沫塑料(EPS)制备胶粘剂;对制备胶粘剂条件作了正交分析,比较了该胶与市售白乳胶的性能差异。结果表明,橙皮提取的精油中柠檬烯质量分数高达96%;V乙酸乙酯/V丙酮/V精油=5/2/3的混合溶剂,对废EPS的溶解力最强。制备胶粘剂最优条件为:乳化剂0.75g,MAA3.0g,酚醛树脂2.0g,BPO0.30g。制备的低毒清香型胶粘剂,剥离强度为0.35kN/m。     

Effects of peel angle on peel force of adhesive tape from soft adherend

In the case of the peeling of adhesive tapes from soft adherends, the contributions of the compressive force at the adhered portion as well as the larger deformation of adherend have essential roles in determining the peeling properties. In this paper, the peel force of an adhesive tape from a soft adherend has been measured to understand the peeling mechanism, which is greatly affected by the peel angle. A commercially available pressure-sensitive adhesive was used as the tape, and a cross-linked polydimethylsiloxane (PDMS) was used as the soft adherend. The purpose of this study is to clarify the effects of the peel angle on the peel behavior of this system at room temperature under different material specifications and different experimental conditions. The factors that affect the peel force of the PDMS adherend included the degree of cross-linking in PDMS, the thickness of PDMS, peel angle, and peel velocity. Two characteristic peel patterns were observed, which depended on the material specifications and different experimental conditions. The peel mechanism was discussed in terms of the deformation of the adherend.     

Adhesion properties of pressure-sensitive adhesives prepared from SMR 10/ENR 25, SMR 10/ENR 50, and ENR 25/ENR 50 blends

The adhesion properties, i.e. viscosity, tack, and peel strength of pressure-sensitive adhesives prepared from natural rubber/epoxidized natural rubber blends were investigated using coumarone-indene resin and toluene as the tackifier and solvent respectively. One grade of natural rubber (SMR 10) and two grades of epoxidized natural rubbers (ENR 25 and ENR 50) were used to prepare the rubber blends with blend ratio ranging from 0 to 100%. Coumarone-indene resin content was fixed at 40 parts per hundred parts of rubber (phr) in the adhesive formulation. The viscosity of adhesive was measured by a HAAKE Rotary Viscometer whereas loop tack and peel strength was determined using a Lloyd Adhesion Tester operating at 30 cm/min. Results show that the viscosity of the adhesive passes through a minimum value at 20% blend ratio. For loop tack and peel strength, it indicates a maximum at 60% blend ratio for SMR 10/ENR 25 and SMR 10/ENR 50 systems. However, for ENR 25/ENR 50 blend, maximum value is observed at 80% blend ratio. SMR 10/ENR 25 blend consistently exhibits the best adhesion property in this study, an observation which is attributed to the optimum compatibility between rubbers and wettability of adhesive on the substrate. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

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.     

Peel Test Using Nonstationary Peel Method

The cohesive peel spectra of pressure-sensitive adhesive (PSA) tapes have been measured using a non-stationary peel tester. The experimental evidence and a viscoelastic analysis based on a peel model indicate that there are no significant effects of acceleration in the normal rate region. The nonstationary peel tester can be regarded as a useful tool for testing and evaluating PSA tapes.     

Peel Test Using Nonstationary Peel Method

The cohesive peel spectra of pressure-sensitive adhesive (PSA) tapes have been measured using a non-stationary peel tester. The experimental evidence and a viscoelastic analysis based on a peel model indicate that there are no significant effects of acceleration in the normal rate region. The nonstationary peel tester can be regarded as a useful tool for testing and evaluating PSA tapes.     

高耐温性钢塑管材用热熔胶黏剂的制备及性能研究

以神华均聚聚丙烯（PP）为基体树脂,通过与聚烯烃弹性体（POE）共混反应挤出制备了高耐温性钢塑管材用热熔胶黏剂。研究了引发剂含量、接枝单体含量和PP/POE配比对热熔胶性能的影响,考察了自制热熔胶在实际应用中的耐温性能。结果表明,反应挤出制备的聚丙烯接枝马来酸酐(PP?g?MAH)基热熔胶综合性能优异,其剥离强度和100 %拉伸弹性回复率分别可达131.4 N/25 mm和65.5 %;高低温循环（-40~130 ℃）800次后自制热熔胶的剥离强度依然可以维持在122.2 N/25 mm,剥离失效率只有7.0 %,其耐温性明显优于选取的两个商业化牌号热熔胶。     

BOND STRENGTH IMPROVEMENT OF POLYURETHANE ADHESIVE BY GRAFTING 2-HYDROXYETHYL METHACRYLATE ON POLYOL BACKBONE

A series of acrylated polyols were prepared by grafting 2-hydroxyethyl methacrylate (HEMA) on to polyol backbone prepared from vegetable oil fatty acid and epoxy resin. Grafting was carried out by free radical mechanism on conjugated double bond present in the polyol using benzoyl peroxide (BPO) as an initiator. Polyols and polyurethane adhesives were characterized by IR spectroscopy. Polyurethane adhesive synthesized from the modified polyols were found to provide better peel strength to styrene butadiene rubber (SBR) joints. Mode of failure was studied using Scanning Electron Microscopy (SEM). Improvement in cohesive strength of the adhesives resulted in high bonding strength. Comparative study has been carried out to determine the effect of acrylation on polyurethane adhesive by Green strength, Curing behavior, and Chemical resistance studies. Loading of 20% HEMA gave significant results. However, 15% loading of HEMA resulted in a sample with highest peel strength.     

Effect of Cross-Linking on Tack and Peel Strength of Polymers

In this work the influence of cross-linking on the adhesive fracture energy and the peel strength is studied choosing polydimethylsiloxane (PDMS) as a model polymer. A series of samples was prepared by electron-beam irradiation which covers the whole range from a viscoelastic liquid to a cross-linked rubber. The mechanical behaviour of these PDMS samples was characterized by mechanical spectroscopy. Tack measurements with an instrument described elsewhere⁵ and peel measurements show that the adhesive fracture energy after short contact times as a measure of tack and the peel strength have a pronounced maximum in the range above the gel point, where the PDMS consists of a very loose and imperfect network and a high fraction of soluble polymer. In this range debonding is connected with the formation of fibrillar structures within the polymer.     

室温固化高剥离耐热环氧树脂胶粘剂

介绍了一种具有高剥离强度和剪切强度的室温固化耐热胶粘剂。室温固化10d后,室温剥离强度可达到7．0kN／m;室温剪切强度为30．8MPa,150℃剪切强度可达14．5MPa。重点讨论了环氧树脂种类、复配合固化剂比例以及促进剂用量对胶粘剂粘接强度和耐热性能的影响。     

Sawtooth-shaped stringiness with front frame formation for polyacrylic pressure-sensitive adhesives with two different molecular structures

The formation of sawtooth-shaped stringiness during 90° peeling was investigated using crosslinked poly(n-butyl acrylate–acrylic acid) and poly(2-ethylhexyl acrylate–acrylic acid) random copolymers with an acrylic acid content of 5 wt.% and different crosslinking degrees as pressure-sensitive adhesives (PSAs). The gel fraction was measured by toluene extraction of PSA, and it increased with crosslinker content for both systems. The observed stringiness was sawtooth-shaped, but there were three different types; both the typical sawtooth shape and the frame formed at the front tip with interfacial failure, and the sawtooth shape formed with cohesive failure. The change in the stringiness shape was affected strongly by the gel fraction of PSA. The peel rate under constant peel load was measured and revealed that the peel rate was lowest upon formation of the front frame type. A good relation was found between peel rate and peel strength, with a greater peel strength upon formation of the front frame type. The concentrated stress at the peeling tip is released by progress of peeling and deformation of the adhesive layer (stringiness) for no frame type. On the other hand, the sufficient interfacial adhesion delays the progress of peeling, and the applied larger stress causes cavitation in the PSA layer for front frame type. The formed cavity grows and the front frame type formed as a result. That is, internal deformation occurred preferentially over peeling. In order to improve the peel strength, the front frame type is the most useful stringiness shape.     

功能单体对冷封胶性能的影响

通过预乳化与连续滴加工艺制备了冷封胶所用纯丙乳液,讨论了功能单体对乳液聚合稳定性、基材粘附力、剥离强度等的影响。结果表明,功能单体与丙烯酸酯类单体一起滴加时,聚合过程稳定,使体系粘接性能有较大提高。     

菱镁板吸塑用聚氨酯胶粘剂的研制

选用低聚物二元醇、二异氰酸酯、二元胺及硅烷偶联剂等合成了菱镁板吸塑聚氯乙烯(PVC)所需的聚氨酯胶粘剂。讨论了多元醇及二异氰酸酯种类、异氰酸酯指数、偶联剂加入方法和用量及胶粘剂相对分子质量等对聚氨酯胶粘性能的影响。结果表明,以聚酯多元醇(PNBA)、甲苯二异氰酸酯(TDI)、扩链剂(IPDA)和偶联剂(KH-550)等原料合成的聚氨酯胶粘剂性能优异,相对分子质量为25 000~40 000,黏度为200 mPa.s~600 mPa.s(固含量30%)。将其喷涂于菱镁板上,真空吸塑PVC后,初黏力大,24 h后终黏剥离强度可达到4.1 N/mm,已达到菱镁板或PVC的破坏程度,满足了使用需要。     

表面处理方法对胶粘剂性能的影响

采用不同的表面处理方法处理粘接接头,在湿热老化条件下通过元素分析法测定了样品中碳、硅、氧的含量,以及对胶粘剂粘接接头剥离强度、吸水率,玻璃化温度等湿热老化性能进行了考查,得出最佳处理粘接接头的方法。     

Adhesive Joint Durability Assessed Using Open-faced Peel Specimens

This paper presents an investigation of the durability of two aluminum-epoxy adhesive systems by means of open-faced peel specimens. A peel analysis model was used to determine the fracture energy from the peel data. Both wet and dry peel tests were conducted in order to distinguish between the reversible and the permanent effects of water. The effects of water on the cohesive properties of the adhesives were also assessed by tension tests. It was found that, for the two-part epoxy adhesive, which plasticized to a large extent, the peel testing should be carried out in a dry state to assess the interfacial weakening. It was also observed that the two-part adhesive was much stiffer in the dry, degraded state, and it was important to take account of such permanent changes in the cohesive properties associated with water uptake when determining the fracture energy from the peel data. In contrast, the one-part epoxy system did not suffer from appreciable cohesive changes, either reversible or permanent. In this case, both wet and dry failure loci were interfacial, and some of the interfacial damage was found to be reversible. Finally, surface analyses of the peel failure surfaces were carried out, and the formation of micro-debonds was identified as a possible mechanism of degradation for the two-part system.