Post-treatment of a polymeric composition
View Patent ↗A post-treatment process for making a water-resistant polymeric composition which is inkjet printable, or in the form of a strongly-swellable gel, includes providing a stable, aqueous two-phase polymeric composition by the steps of forming a reaction mixture in a reaction vessel which includes a water-soluble vinyl monomer, optionally with one or more water-soluble comonomers, a first amount of a multi-vinyl crosslinking agent, and water, heating the mixture, then periodically adding a predetermined amount of a free radical initiator, and polymerizing the reaction mixture, optionally removing the resultant two-phase polymeric composition from the reaction vessel, adding a predetermined amount of a post-treatment crosslinker, optionally blending with a proteinaceous or other water compatible polymer material thereto, optionally coating the mixture onto a support, and optionally heating at room temperature or above, to increase the viscosity of the composition in a predetermined manner.
1. A past-treatment process for making an inkjet printable, polymeric composition or a strongly-swellable polymeric hydrogel which comprises providing a stable, aqueous two-phase polymeric composition by the steps of forming a reaction mixture in a reaction vessel of a water-soluble vinyl monomer, optionally with one or more water-soluble comonomers, a predetermined amount of a first crosslinking agent, and water, heating the mixture, then periodically adding a predetermined amount of a free radical initiator, and polymerizing at a suitable temperature, optionally removing said resultant two-phase polymeric composition from the reaction vessel, including an added active material, adding a predetermined amount of a post-treatment crosslinker, optionally blending a proteinaceous and/or water compatible material thereto, optionally coating the mixture onto a support, and optionally heating the mixture.
2. A process according to claim 1 which produces an inkjet printable polymeric composition capable of forming a water-resistant polymeric coating on a substrate.
3. A process according to claim 1 which produces a hydrogel composition.
4. A process according to claim 1 in which said two-phase composition is post-treated with said post-treatment crosslinker at a temperature from room temperature to about 200° C.
5. A process according to claim 1 in which at least 0.02% by weight of said post-treatment crosslinker is added to the two-phase composition.
6. A process according to claim 1 which includes a proteinaceous material.
7. A process according to claim 1 in which said first polymerization crosslinker is present in an amount of 0.02-0.5 wt. % based on monomers.
8. A process according to claim 1 which produces a strongly-swellable hydrogel having a Brookfield viscosity of at least 100,000 cps.
9. A process according to claim 1 where the active material is present and is a cosmetic, nutritional or pharmaceutical active material.
10. A process according to claim 1 in which said water compatible material is polyvinyl alcohol, 2-ethyl-2-oxazolidone or polyethylene oxide.
11. A process according to claim 1 wherein said comonomer is dimethylaminopropyl(meth)acrylamide, dimethyl aminoethyl(meth) acrylate and/or hydroxyl ethyl(meth) acrylate.
12. A process according to claim 1 wherein the post-treatment crosslinker is an aziridine, 1-aziridine ethanol, glycidol, a glycerol glycidyl ether, tris(2,3-epoxypropyl) isocyanurate, trimethylolpropane triglycidyl ether, diglycidyl ether of 1,4 butanediol, diglycidyl 1,2-cyclo-hexanecarboxylate, neopentyl glycol diglycidyl ether, 3-glycidoxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl) ethyltriethoxysilane, glycerol propoxylate triglycidyl ether or glycidol, or boric acid.
13. A process according to claim 11 wherein said post-treatment crosslinker includes at least 2 crosslinking sites in the molecule.
14. A process claim 13 in which said post-treatment crosslinker is a polyfunctional epoxy or oxirane.