摘要:
This invention relates to improved crosslinking systems for polymeric dispersions and solutions having suitability for coatings, adhesives and use in many other applications. These systems are based upon crosslinkable polymers having a plurality of activated keto methylene groups, e.g., a beta diketone such as an acetoacetate or a keto cyano methylene functional groups and a crosslinkable component comprising an aldimine. A sufficient amount of the aldimine curing agent is used to effect reaction with the polymer containing the activated keto methylene groups and cure thereof. The improvement in the crosslinking system resides in the utilization of a monoaldimine having only one aldimine group and no other methylene reactive group as a crosslinking agent. Another improvement variation to that previously suggested comprises a redispersible polymer(s) containing activated methylene functionality and combined with the monoaldimine and the use of heterocyclic aldimine.
摘要:
Novel unsaturated compounds comprising the 3-(N-vinylformamido)propionates and 2-methyl-3-(N-vinylformamido)propionates are obtained by the Michael addition reaction of N-vinylformamide with an acrylic or methacrylic acid ester. These compounds are useful as monomers in free radical polymerizations, particularly as components of photocurable coatings.
摘要:
The wet strength of cellulosic paper is improved by adding the combination of an amine-functional poly(vinyl alcohol) and a cellulose reactive size which is a 4 or 5 membered cyclic ester or anhydride having alkyl or alkenyl substituents of 4 or more carbon atoms. The amine-functional polymer is preferably a hydrolyzed copolymer of vinyl acetate and N-vinylformamide in which about 1-25 mole % of the monomer units are incorporated N-vinylformamide, and the cellulose reactive size is preferably an alkyl ketene dimer or an alkenyl succinic anhydride. A paper product is provided having improved wet-strength and containing normally 0.05 to 4.0 wt % based on the dry pulp of the additive amine-functional polymer and cellulose reactive size. The particular compounds which represent the polymer and the size cooperate to provide improvements in wet-tensile strength for paper which could not have been foreseen from the effects of either material acting alone.
摘要:
Fluid coating materials such as paints, ink pastes, personal care creams and the like having a water-base are thickened with an associative thickener which is a vinylamine polymer having a weight average molecular weight above 10.sup.5 and which has been modified by reaction with at least 0.2 mer percent of a linear monoaldehyde having 8 to 30 carbon atoms. A hydrolyzed polymer of N-vinylformamide which has been hydrophobically modified with an aldehyde such as dodecaldehyde, exhibits associative thickening characteristics and is useful in thickening water-based formulations.
摘要:
Vinyl acetate and an N-vinyl formamide are copolymerized to yield poly(vinyl acetate)-co-poly(N-vinyl formamide) which is base hydrolyzed to poly(vinyl alcohol)-co-poly(N-vinyl formamide). Two phase hydrolysis of particles of poly(vinyl alcohol)-co-poly(N-vinyl formamide) as a slurry in methanol yields particles of poly(vinyl alcohol)-co-poly(vinylamine).Provided is a copolymer of the following general formula ##STR1## where m is 0 to 15 mole %,n is 50 to 99 mole %, x is 0 to 30 mole %, and y is 1 to 50 mole %.
摘要:
Vinyl acetate and an N-vinyl formamide are copolymerized to yield poly(vinyl acetate)-co-poly(N-vinyl formamide) which is base hydrolyzed to poly(vinyl alcohol)-co-poly(N-vinyl formamide). Two phase hydrolysis of particles of poly(vinyl alcohol)-co-poly(N-vinyl formamide) as a slurry in methanol yields particles of poly(vinyl alcohol)-co-poly(vinylamine).provided is a copolymer of the following general formula ##STR1## where m is 0 to 15 mole %. n is 50 to 99 mole %.x is 0 to 30 mole %. andy is 1 to 50 mole % .
摘要:
Vinylamide oligomers and lower molecular weight polymers are prepared by the cationic polymerization of vinylamides in the presence of a Lewis acid at a temperature between -100.degree. and 100.degree. C. The resultant vinylamide oligomers and polymers can optionally be hydrolyzed under acidic or basic conditions to form the corresponding vinylamine oligomers and polymers.
摘要:
Polyvinylaminals, optionally as the formed copolymer with polyvinylhemiaminals and polyvinylacetals are useful as separating agents and are provided by reacting a poly(vinylamine) or a copolymer containing vinyl alcohol and vinylamine units with a monoaldehyde. The aldehyde, such as butyraldehyde, can be introduced into the polymer aminalization as a liquid or gas, generally in a proportion of about 0.02 to 0.5 mol per mol of alcohol and amine units in the polymer chain. These polymers, especially as the cationic salt, perform very well in the flocculation, settling, clarification and dewatering of wastewater.
摘要:
This invention relates to an improvement in a process for producing a latex containing dispersed polymer. The improvement in the process for polymerizing a reaction mixture of vinyl monomer, stabilizer, oxidizing agent and reducing agent comprises using a water-soluble ketone bisulfite as the reducing agent, either alone or with other reducing agents, the ketone having from 3 to 8 carbon atoms in the structure. During the polymerization, the ketone bisulfite is maintained in stoichiometric excess of the oxidizing agent. Vinyl acetate-ethylene copolymers are some of the preferred polymer systems produced.