Spray drying method for solid epoxy or phenoxy resin

Abstract

A high molecular weight solid epoxy or phenoxy resin is dissolved in a blend of alcoholic and aprotic solvents, and the resulting solution is spray dried in a closed-cycle spray dryer to form a powdered epoxy or phenoxy resin.

Claims

1. A method for forming a dry powdered thermoplastic resin composition, the following: A solid thermoplastic resin selected from the group consisting of solid epoxy resins and solid phenoxy resins is dissolved in a blend of a C1-C4-alkanol protic solvent and an aromatic aprotic solvent to form a slurry, wherein the amount of the aprotic solvent exceeds the amount of the protic solvent by at least 1% by weight, and The slurry is spray-dried to form the dried powdered thermoplastic resin composition, Includes, The aforementioned dry powdered thermoplastic resin composition contains a residual solvent content of 5% (w / w) or less. The aforementioned method.

2. The method according to claim 1, wherein the solid epoxy resin includes bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol AF epoxy resin, o-cresol novolak epoxy resin, phenol novolak epoxy resin, modified phenol epoxy resin, naphthalene epoxy resin, triphenolmethane epoxy resin, alkyl-modified triphenolmethane epoxy resin, triazine nucleus-containing epoxy resin, dicyclopentadiene epoxy resin, glycidylamine epoxy resin, biphenyl epoxy resin, biphenyl aralkyl epoxy resin, hydrogenated bisphenol A epoxy resin, aliphatic epoxy resin, stilbene epoxy resin, trisphenol-methane triglycidyl ether, isocyanate-modified bisphenol A epoxy resin, isocyanate-modified bisphenol F epoxy resin, isocyanate-modified bisphenol AF epoxy resin, isocyanate-modified bisphenol A novolak epoxy resin, bisphenol F novolak epoxy resin, bisphenol AF novolak epoxy resin, or a combination thereof.

3. The solid phenoxy resin has the following structural formula 【Chemistry 1】 In the formula, n is an integer between approximately 8 and approximately 400, and X is as follows: 【Chemistry 2】 Selected from, The method according to claim 1.

4. The method according to claim 1, wherein the slurry contains about 5% to about 10% by weight of epoxy or phenoxy resin, based on the total weight of the slurry.

5. The method according to claim 1, wherein the solid phenoxy resin is obtained by a condensation reaction of a divalent phenol compound and epichlorohydrin, or by a polyaddition reaction of a divalent phenol compound and a bifunctional epoxy resin.

6. The method according to claim 1, wherein the slurry is spray-dried in a closed-cycle spray-drying apparatus.

7. A method for forming a dry powdered thermoplastic resin, the following: A solid thermoplastic resin selected from solid phenoxy resins is dissolved in a blend of a C1-C4-alkanol protic solvent and an aromatic aprotic solvent to form a slurry, wherein the amount of the aprotic solvent exceeds at least 1% by weight of the amount of the protic solvent, and The process includes spray-drying the slurry to form the dried powdered thermoplastic resin composition, The dried powdered thermoplastic resin composition contains a plurality of phenoxy resin particles having an average particle size of about 3 μm to about 25 μm and a residual moisture content of about 0.01% (w / w) to about 1.5% (w / w), and the spray drying is performed using a closed-cycle spray drying apparatus. The aforementioned method.

8. A method for forming powdered epoxy or phenoxy resin, the following: Prepare a solid epoxy or phenoxy resin with an average molecular weight of at least approximately 1000 daltons, The solid epoxy or phenoxy resin is dissolved in a blend of an alcohol solvent which is a C1-C6-alkanol and an aromatic aprotic solvent to form a solution, wherein the blend has a weight ratio of the alcohol solvent to the aromatic aprotic solvent such that the amount of the aprotic solvent is at least 1% by weight of the protic solvent, and the resulting solution contains about 1% to about 10% by weight of epoxy or phenoxy resin based on the total weight of the resulting solution, and The obtained solution is spray-dried in a closed-cycle spray dryer to form a powdered epoxy or phenoxy resin containing a residual solvent content of 5% (w / w) or less. including, The aforementioned method.

9. The method according to claim 8, wherein the solid epoxy or phenoxy resin has an average molecular weight of at least about 10,000 daltons.

10. The method according to claim 8, wherein the alcohol solvent is selected from the group consisting of ethanol, propanol, isopropanol, butanol, pentanol, and hexanol, and the aprotic solvent is selected from the group consisting of methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, dichloromethane, and tetrahydrofuran.

11. The resulting solution contains about 5% to about 10% by weight of epoxy or phenoxy resin. The method according to claim 8.

12. The method according to claim 8, wherein the powdered epoxy or phenoxy resin has an average particle size of about 20 μm or less.

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