Cured Phenolic Spheres and Method of Producing the Same

Patent metadata

Field	Value
Publication number	US-2016229944-A1
Application number	US-201615041070-A
Country	US
Kind code	A1
Filing date	Feb 11, 2016
Priority date	Feb 11, 2015
Publication date	Aug 11, 2016
Grant date	—

Abstract

A process for the production of high compressive strength microspheres of cured phenolic resins are disclosed. Specifically, the microspheres formed by this process exhibit excellent viscoelastic properties in that the microspheres retain their shape even after applying a load of at least 4 GPa at 2.5 percent strain, and exhibit high hardness of at least about 0.3 GPa.

First claim

What is claimed is:

1 . A process for the production of cured phenolic spheres having an average particle diameter of greater than 100 microns, comprising:
reacting a phenolic compound and an aldehyde in an aqueous medium in the presence of a basic catalyst and an emulsion modifier, at a temperature from about 95-105° C.

2 . The process of claim 1 , wherein the emulsion modifier is selected from the group consisting of partially hydrolyzed polyvinyl acetate and gum Arabic.

3 . The process of claim 1 , wherein the emulsion modifier is a polyvinyl acetate which is at least 90 percent hydrolyzed.

4 . The process of claim 1 , wherein the molar ratio of the aldehyde to phenolic compound is higher than 1.

5 . The process of claim 1 , wherein the molar ratio of the aldehyde to phenol is from about 1 to about 3.

6 . The process of claim 1 , wherein parts of the basic catalyst is at least 2 parts per 100 parts of the phenolic compound.

7 . The process of claim 1 , wherein parts of the basic catalyst is from about 2 to 5 parts per 100 parts of the phenolic compound.

8 . The process of claim 1 , wherein the polyvinyl acetate is hydrolyzed from about 91% to 94% and is present in the amount of 0.1 to 12 parts of phenolic compound.

9 . The process of claim 1 , wherein the phenolic compound is selected from the group consisting of phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, resorcinol, bisphenol-A and bisphenol-S.

10 . The process of claim 1 , wherein the aldehyde is selected from the group consisting of formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, iso-butyraldehyde, glyoxal and furfural.

11 . The process of claim 1 , wherein the phenolic compound is phenol and the aldehyde is formaldehyde.

12 . The process of claim 11 , wherein phenol and formaldehyde in the aqueous medium in the presence of the basic catalyst and the emulsion stabilizer is stirred at a stirrer speed of 20 to 400 rpm.

13 . The process of claim 1 , wherein the reaction is carried out for a period of 3-7 hours.

14 . A spherical cured phenolic resin produced by the process of claim 1 .

15 . A spherical cured phenolic resin composition having an average particle diameter greater than about 100 μm, which particles exhibiting a compressive strength of at least 4 GPA at a strain of about 2.5 percent and an average hardness of at least 0.3 GPa.

16 . The composition of claim 15 , wherein the average particle diameter of the microspheres is in the range from about 200 to about 300 μm.

17 . The composition of claim 15 , wherein the phenolic resin comprises a phenolic compound, an aldehyde, polyvinyl acetate which is at least 90% hydrolyzed and a base catalyst.

18 . The composition of claim 17 , wherein the phenolic compound is selected from the group consisting of phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, resorcinol, bisphenol-A and bisphenol-S.

19 . The composition of claim 17 , wherein the aldehyde is selected from the group consisting of formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, iso-butyraldehyde, glyoxal and furfural.

20 . The composition of claim 17 , wherein the phenolic compound is phenol and the aldehyde is formaldehyde.

Assignees

• Durez Corp
• Sumitomo Bakelite Co

Inventors

• Warakomski Todd
• Yoshihiro Matsuo

Classifications

• C08J2361/10

  Phenol-formaldehyde condensates · CPC title

• C08J2429/04

  Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids · CPC title

• C08G8/10 Primary

  with phenol · CPC title

• C08J5/00

  Manufacture of articles or shaped materials containing macromolecular substances (manufacture of semi-permeable membranes B01D67/00 - B01D71/00) · CPC title

• C08L61/06

  of aldehydes with phenols · CPC title