Method for manufacturing thermoplastic resin composition
A method for manufacturing a thermoplastic resin composition enabling easy control of the weight average molecular weight of a thermoplastic resin used in a soluble three-dimensional modeling support material, the support material having sufficient strength even when used in the manufacture of a three-dimensional object by an FDM system 3D printer, being less colored with excellent appearance quality, and having a high dissolution speed in neutral water and quickly removable from a precursor of the three-dimensional object without using a strong alkaline aqueous solution; and the thermoplastic resin having dicarboxylic acid monomer units derived from a dicarboxylic acid component and having a proportion of an aromatic dicarboxylic acid monomer unit derived from a sulfonic acid group and/or sulfonate group-containing aromatic dicarboxylic acid component in the dicarboxylic acid monomer units of 10 mol % or more; the method including mixing an organic salt compound represented by formula (I): (R 1 —SO 3 − ) n X n+ (I).
1. A method for manufacturing a thermoplastic resin composition comprising a thermoplastic resin, the method comprising:
mixing an organic salt compound during preparation of the thermoplastic resin;
wherein:
the thermoplastic resin comprises dicarboxylic acid monomer units derived from at least one dicarboxylic acid component;
the dicarboxylic acid monomer units comprise aromatic dicarboxylic acid monomer units derived from at least one selected from the group consisting of a sulfonic acid group-containing aromatic dicarboxylic acid component and a sulfonate group-containing aromatic dicarboxylic acid component;
the thermoplastic resin comprises the aromatic dicarboxylic acid monomer units in an amount of 10 mol % or more based on a total amount of the dicarboxylic acid monomer units in the thermoplastic resin;
the thermoplastic resin comprises the aromatic dicarboxylic acid monomer units in an amount of 8 to 45 mol % based on a total amount of monomer units in the thermoplastic resin;
the thermoplastic resin has a weight average molecular weight (M w ) of 16,000 to 35,000; and
the organic salt compound comprises a compound according to formula (I):
(R 1 —SO 3 − ) n X n+ (I)
wherein:
R 1 represents a hydrocarbon group that may have a substituent and has 1 to 30 carbon atoms;
n represents a number of 1 or 2;
when n is 1, X n+ represents a sodium ion, a potassium ion, a lithium ion, an ammonium ion, or a phosphonium ion; and
when n is 2, X n+ represents a magnesium ion, a calcium ion, a barium ion, or a zinc ion.
2. The method for manufacturing a thermoplastic resin composition according to claim 1 , wherein the mixing comprises adding the organic salt compound at a mole ratio of 0.005 or more relative to a total amount of the aromatic dicarboxylic acid monomer units in the thermoplastic resin.
3. The method for manufacturing a thermoplastic resin composition according to claim 1 , wherein the dicarboxylic acid monomer units comprise non-hydrophilic dicarboxylic acid monomer units derived from at least one non-hydrophilic group-containing dicarboxylic acid component in an amount of 5 to 45 mol % based on the total amount of monomer units in the thermoplastic resin.
4. The method for manufacturing a thermoplastic resin composition according to claim 1 , wherein the mixing comprises adding the organic salt compound during polymerization to form the thermoplastic resin.
5. The method for manufacturing a thermoplastic resin composition according to claim 1 , wherein the thermoplastic resin comprises at least one selected frog the group consisting of sulfonic acid groups and sulfonate groups in a total amount of 0.5 mmol/g or more and 3.0 mmol/g or less.
6. The method for manufacturing a thermoplastic resin composition according to claim 1 , wherein the thermoplastic resin is a polyester resin or a polyamide resin.
7. The method for manufacturing a thermoplastic resin composition according to claim 6 , the mixing comprises mixing the organic salt compound with the at least one dicarboxylic acid component and at least one selected from the group consisting of a diol component and a diamine component.
8. The method for manufacturing a thermoplastic resin composition according to claim 1 , wherein:
X n+ represents a phosphonium ion; and
the phosphonium ion is a tetraalkylphosphonium ion.
9. The method for manufacturing a thermoplastic resin composition according to claim 1 , wherein the mixing comprises adding the organic salt compound at a mass ratio of 0.5 to 30% relative to a mass of the thermoplastic resin.
10. The method for manufacturing a thermoplastic resin composition according to claim 1 , wherein the mixing comprises adding the organic salt compound in an amount such that a molar ratio of alkylsulfonic acid ions (R 1 —SO 3 − ) in the organic salt compound to hydrophilic groups in the thermoplastic resin is 0.005 to 1.0.
11. A soluble material for three-dimensional modeling comprising a thermoplastic resin composition obtained by the method for manufacturing a thermoplastic resin composition according to claim 1 .
12. A method for manufacturing a three-dimensional object by a fused deposition modeling system, the method comprising:
obtaining a precursor of the three-dimensional object comprising the three-dimensional object and a support material; and
removing the support material by bringing the precursor of the three-dimensional object into contact with neutral water;
wherein the support material comprises the soluble material for three-dimensional modeling according to claim 11 .