• Polymer(Korea)
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• v.32 no.4
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• pp.313-321
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• 2008

Acrylic pressure sensitive adhesive(PSA) was prepared by UV radiation curing and the peel energy and physical properties of PSA were investigated. The increase of amount of acrylic acid leads to improve the peel energy, associated with the substrate having smooth surface and high layer thickness. The high peel energy is obtained when the direction of irregularity in substrate is horizontal with the peeling direction. This is attributed to the increase of resistance to peeling in spite of decrease of wetting and the result corresponds to our supposition.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.1
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• pp.85-92
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• 1994

With the wide application of fiber-reinforced composite meterial in aircraft space structures and robot arms, the design and manufacture of composite joints have become a very important research area because they are often the weakest areas in composite structure. In this paper, the torque transmission capacities of the adhesive tubular single lap joint and double lap joint were studied. The stress and torque transmission capacity of the adhesive joints were analyzed by the finite element method and compared to the experimental results. The torque capacity of the double lap joint was increased 2.7 times over that of the single lap joint. Also, the fatigue limit of the double lap joint was increased 16 times over that of the single lap joint.

• Polymer(Korea)
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• v.39 no.3
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• pp.514-521
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• 2015

In this study, we would like to describe peel strength and dynamic shear property on various substrates of multi-layered structural double-sided adhesive tape with or without adhesive (AD) prepared by UV curing for an automobile, construction, and display junction. According to adapt the adhesive, the peel and dynamic shear strength of adhesion tape prepared with acrylic foam or various plastic substrates increased with increasing molecular weight, however, decreased over 650000 molecular weight. The adhesion property shows high value at the thin AD layer with decreasing temperature. The interface property shows highest at MW 615000 (AD-4), and the interface junction below MW 615000 resulted to divide from acrylic foam and adhesive layer. From this study, the multi-layered structural double-sided adhesive tapes seem to be a useful for industrial area such as a low surface energy plastic material and curved substrate.

• Applied Chemistry for Engineering
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• v.9 no.4
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• pp.491-496
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• 1998

The composition of isocyanates and polyols influence prepolymeric properties of adhesive and calking sealant based on polyurethanes (PU). One component moisture curing prepolymers, which reacted with surface humidity of substrate, were synthesized in several kinds of composition. Reactivity, structural change and properties of the prepolymers were studied as a preliminary step to manufacture PU based adhesive and sealant. To study the effects of mole ratio ([NCO]/[OH]), we used toluene diisocyanate (TDI), 4, 4'-diphenylmethane diisocyanate (MDI), and ether-polyols such as PTMG and PPG which have good resistance to hydrolysis and excellent low-temperature properties. The each prepolymers could be prepared in different molecular weight without any significant structural change. The mole ratio 1.78 of [NCO] to [OH] showed the fastest reactivity. It was confirmed that effect of polyols was larger than that of isocyanates on the prepolymer in reactivity. Several kinds of compounds were manufactured with each prepolymer, and tensile and properties were tested. And the optimum quantity of curing accelerator for the PU was 0.05~0.1%. In the tensile test, TDI based PU was superior to MDI based PU, and also PTMG based PU was superior PPG based PU.

• Journal of Adhesion and Interface
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• v.2 no.3
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• pp.25-32
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• 2001

Ethyl cyanoacrylate (ECA) is used as an instant adhesive, and it can be readily polymerized by moisture in air without any initiator and applied for industrial products and ohome use. However, pure ECA monomer is low-viscosity liquid at room temperature that flows into substrate surface. To thicken the instant adhesive, poly(methyl methacylate)(PMMA) is often added in it commercially. Another disadvantage of instant adhesive polymer is its brittleness In this study, functional polymers including PMMA for an additive of ECA were prepared to increase viscosity of the monomer and flexibility of the adhesive atthe same time The additives, P(MMA-VAc-EVE), were synthesized by radical copolymerization of MMA with VAc and EVE having low glass transition temperature (Tg). The additives were added to ECA to get functional instant adhesives. The chemical structures of the additives and ECA polymers were confirmed by $^1H$ NMR and FTIR, and their physical and mechanical properites were also evaluated. The Tg of the obtained additives decreased with increasing the content of VAc or VAc-EVE, indicating more improved flexibility. In addition, functional instant adhesive containing the additives showed higher bonding strength than that of the existing one.