Patent ID: 11905364
Assignee: SOLVAY SPECIALTY POLYMERS USA, LLC
Field: Other special machines (Mechanical engineering)
Classification: CPC C  B | IPC B  C

Claim 0:
1. A process for preparing particles of polyphenylene sulfide polymer (PPS), comprising the following steps:
melt-blending a mixture (M) comprising:
a) at least one PPS, and
b) at least one water-dispersible polyester polymer (PE) comprising units from:
at least one aromatic dicarboxylic acid component comprising:
at least one aromatic dicarboxylic acid selected from the group consisting of isophthalic acid (IPA), terephthalic acid (TPA), naphthalenedicarboxylic acid, 4,4′-bibenzoic acid, 2,5-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 3,5-pyridinedicarboxylic acid, 2,2-bis(4-carboxyphenyl)propane, bis(4-carboxyphenyl)methane, 2,2-bis(4-carboxyphenyl)hexafluoropropane, 2,2-bis(4-carboxyphenyl)ketone, 4,4-bis(4-carboxyphenyl)sulfone, 2,2-bis(3-carboxyphenyl)propane, bis(3-carboxyphenyl)methane, 2,2-bis(3-carboxyphenyl)hexafluoropropane, 2,2-bis(3-carboxyphenyl)ketone, bis(3-carboxyphenoxy)benzene, and mixtures thereof, and

an aromatic dicarboxylic acid containing at least one SO3M group attached to an aromatic nucleus, wherein M is H or a metal ion selected from the group consisting of sodium, lithium and potassium,
at least one diol component wherein the at least one diol is selected from the group consisting of ethylene glycol, diethylene glycol 1,4-cyclohexanedimethanol, propane-1,2-diol, 2,2-dimethyl-1,3-propanediol and mixtures thereof, and at least 50 mol. % of the diol component, this proportion being based on the total number of moles of the diol component, is the diethylene glycol, and

processing the mixture (M) into pellets or strands,
cooling the pellets or strands at a temperature below 80° C.,
contacting said pellets or strands with water, optionally heated to a temperature up to 95° C. to provide particles,
recovering the particles,
optionally drying the particles, and
optionally sieving the particles;
wherein the step of melt-blending takes place at a temperature above 250° C. and the particles of PPS have a D50 comprised between 5 μm and 100 μm.