摘要:
A process for preparing methyl .alpha.-cyanoacrylate in which methyl cyanoacetate is reacted with formaldehyde to form a polymer, which is subsequently depolymerized to the monomeric product, comprises using an ester of poly(ethylene glycol) as the solvent for the polymerization and depolymerization reactions.
摘要:
A N-substituted piperazine or N-substituted homopiperazine adduct with a polyepoxide is used as a co-curing agent in epoxy resin systems containing a polyepoxide and a known curing agent such as dicyandiamide, a carboxylic acid anhydride, or a dihydrazide. The preferred adducts have a ratio of epoxy groups to secondary amino groups of between 1.2:1 and 3:1. The preferred polyepoxides are polyglycidyl ethers of 4,4'-isopropylidenediphenol (bisphenol A). Suitable adducts are prepared from N-methyl-, N-(2-hydroxyethyl)-, N-octyl-, N-phenyl- and N-benzyl piperazine and N-methyl homopiperazine.
摘要:
Improved 2-cyanoacrylate adhesive compositions containing acetic acid exhibit greatly enhanced bond strength with no significant reduction in cure rate. Such compositions may be used on a wide variety of substrates and are particularly useful on metals.
摘要:
A hot-melt adhesive especially useful in the construction of disposable diapers contains a vinyl polymer of 40-90% by weight of a C.sub.1 -C.sub.12 alkyl acrylate and 10-60% by weight of an alpha-olefin of C.sub.20 -C.sub.40, wherein the alkyl acrylate may be partially replaced with vinyl acetate or with a C.sub.6 -C.sub.12 olefin or with mixtures thereof, provided that the polymer contain at least 10% by weight of the alkyl acrylate. The adhesive may also contain a tackifying resin, a wax, an oil or a stabilizer depending on the specific end-use desired. In a preferred embodiment the polymer contains 20-45% by weight of the alpha-olefin.
摘要:
A copolyester is formed of at least one symmetrical aromatic dicarboxylic acid member, at least one dimer acid, and at least one C.sub.2 --C.sub.10 glycol, and at least one polyester polyol member. The polyester polyol member is either a polycaprolactone polyol having a molecular weight of 500-5,000, or a mixture of a polycaprolactone diol having a molecular weight of 300-5,000 and a nonpolymeric polyol. The resultant thermoplastic copolyester has a glass transition temperature of less than 25.degree.C and a polymer melting temperature greater than 70.degree.C, and is useful both as a hot melt adhesive by itself and as an ingredient of both pressure sensitive and non-pressure sensitive hot melt adhesive formulations. In producing the copolyester, an intermediate copolyester of the symmetrical aromatic dicarboxylic acid member, the dimer acid, and the glycol is chain extended by reaction with the polyester polyol member in a 2-6 hour reaction at about 225.degree.-270.degree.C under a vacuum of about 1-30 mm. Hg. pressure.
摘要:
A hot-melt adhesive especially useful in the construction of disposable diapers contains a vinyl polymer of 40-90% by weight of a C.sub.1 -C.sub.12 alkyl acrylate and 10-60% by weight of an alpha-olefin of C.sub.20 -C.sub.40, wherein the alkyl acrylate may be partially replaced with vinyl acetate or with a C.sub.6 -C.sub.12 olefin or with mixtures thereof, provided that the polymer contain at least 10% by weight of the alkyl acrylate. The adhesive may also contain a tackifying resin, a wax, an oil or a stabilizer depending on the specific end-use desired. In a preferred embodiment the polymer contains 20-45% by weight of the alpha-olefin.
摘要:
Starch-based alkaline curing corrugating adhesives, containing a novel crosslinking additive comprising acetoacetamide-formaldehyde condensate, are useful in the manufacture of corrugated paperboard. These adhesives are characterized by their excellent stability with respect to viscosity, their long pot life and their ability to form water-resistant bonds, particularly after aging.
摘要:
Improved storage-stable anaerobic curing adhesive compositions useful as anaerobic adhesives and sealants are prepared by first mixing a polymerizable acrylate ester monomer, an inhibitor for free radical polymerization, a chelator, and at least an effective amount of an accelerator system consisting of an N-substituted sulfonamide and an aromatic tertiary amine. The resultant homogeneous mixture is thereafter maintained at a temperature of at least about 20.degree. C. for a period of time sufficient to provide the composition with anaerobic curing properties and a specified minimum amount of active oxygen. In one embodiment, the mixture is stirred at a temperature of 45.degree.-80.degree. C. for 10-30 hours. In another embodiment, the mixture is maintained at an elevated temperature without stirring.
摘要:
The invention provides disulfonimide compounds of the general formula ##STR1## wherein X is bromine, chlorine or iodine; R is hydrogen or methyl; and R' is alkyl, aryl or substituted aryl. The compounds are useful as activators for anaerobic adhesive compositions and also as intermediates in the preparation of monomers of the general formula ##STR2## wherein R and R' are as defined above. The monomers are polymerizable to form homo- and copolymers useful in the photographic industry as well as in formulating anaerobic adhesive compositions.
摘要:
Photoconductive coating compositions for application to solid substrates which are to be utilized in electrophotographic operations are described; the resultant photoconductive coatings comprise a layer of photoconductive pigment particles bonded to themselves and to the solid substrate with a binder comprising a novel interpolymer, at least one of whose constituent monomers contains bromine. Novel bromine-containing monomers are also disclosed.