Acryhc reaction adhesive

Acryhc stmctural adhesives have been modified by elastomers in order to obtain a phase-separated, toughened system. A significant contribution in this technology has been made in which acryhc adhesives were modified by the addition of chlorosulfonated polyethylene to obtain a phase-separated stmctural adhesive (11). Such adhesives also contain methyl methacrylate, glacial methacrylic acid, and cross-linkers such as ethylene glycol dimethacrylate [97-90-5]. The polymerization initiation system, which includes cumene hydroperoxide, N,1S7-dimethyl- -toluidine, and saccharin, can be apphed to the adherend surface as a primer, or it can be formulated as the second part of a two-part adhesive. Modification of cyanoacrylates using elastomers has also been attempted copolymers of acrylonitrile, butadiene, and styrene ethylene copolymers with methylacrylate or copolymers of methacrylates with butadiene and styrene have been used. However, because of the extreme reactivity of the monomer, modification of cyanoacrylate adhesives is very difficult and material purity is essential in order to be able to modify the cyanoacrylate without causing premature reaction. 

Surface oxidation reactions have been carried out on a number of polymers, particularly polyethylene. Surface oxidation techniques include the use of corona discharge, ozone, hydrogen peroxide, nitrous acid, alkaline hypochloride, UV irradiation, oxidizing flame, and chromic acid The reactions lead initially to the formation of hydroperoxides, which catalyze the formation of aldehydes and ketones and finally, acids and esters. Surface oxidation treatment has been used to increase the printabdity of polyethylene and poly(ethylene terephthalate) and to improve the adhesion of polyethylene and polypropylene to polar polymers and that of polytetrafluoroethylene to pressure-sensitive tapes. Surface-oxidized polyethylene, when coated with a thin film of vinylidene chloride, acrylonitrile, and acryhc acid terpolymers becomes impermeable to oxygen and more resistant to grease, oil, abrasion, and high temperatures. The greasy feel of polyethylene has also been removed by surface oxidation. 

Acryhc derivatives of 5,6-dihydrodicyclopentadiene could be appUed as the reactive diluents for coating and adhesive compositions to replace high volatile ahphatic acrylates. They could be synthesized from acrylic acid and DCPD in the presence of acidic catalysts and inhibitors (e.g. hydroquinone) (Fig. 11) [35] or in acrylic acid esterification with the reaction product of DCPD with water or glycol in the presence of acidic catalyst (e.g. BF3 or p-toluenesulfonic acid) (Fig. 12) [36,37] ... 

Where the hardening of an adhesive or sealant proceeds by chemical reaction, the rate will increase with temperature in accordance with the Arrhenius equation. Such materials include epoxides, structural acryhcs, cyanoacrylates, silicones, and high temperature adhesives. Hence, pot life and cure time will show the following proportionality ... 

We have already indicated that incompatibility in polymer blends causes distinct regions called microphases. The most important factor governing the mechanical properties of blends is the interfacial adhesion between microphases. One of the techniques to improve this adhesion is to bind the separate microphases through chemical reaction of functional groups. Figure 2.3 shows a styrene copolymer containing oxazoline groups and an ethylene copolymer with acryhc acid as a comonomer. These polymers are represented as follows ... 

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