GERM-REPELLENT COMPOSITION AND PREPARATION METHOD THEREOF
A germ-repellent composition and preparation method are disclosed in the present disclosure. The germ-repellent composition introduces germ-repellent properties into a copolyester suitable for food processing and enhances its germ-repellent structure. The germ-repellent composition comprises a bio-based copolyester and a functional modifier comprising a germ-repellant agent, a reinforcing filler, and a dispersing agent. The method comprises a step of mixing the bio-based copolyester with the functional modifier by thermal processing. The present application provides transparent, colorless, mechanically tough, and heat-resistant germ-repellent copolyester.
1 . A germ-repellent composition, comprising:
a bio-based copolyester; and
a functional modifier comprising,
a reinforcing filler comprising at least one inorganic oxide,
a dispersing agent encapsulating the reinforcing filler, wherein the dispersing agent comprises at least one stearate salt, and
a germ-repellent agent, wherein the germ-repellent agent binds to the dispersing agent.
2 . The composition of claim 1 , wherein the bio-based copolyester is a terephthalic acid copolymer.
3 . The composition of claim 2 , wherein the terephthalic acid copolymer comprises of terephthalic acid and at least one comonomer selected from the group consisting of 1,4:3,6-dianhydro-D-glucitol, 1,4-cyclohexane dimethanol, and 1,2-ethanediol.
4 . The composition of claim 1 , wherein the inorganic oxide is selected from zinc oxide and silicon oxide.
5 . The composition of claim 1 , wherein the stearate salt is selected from calcium stearate and zinc stearate.
6 . The composition of claim 1 , wherein the germ-repellent agent is selected from the group consisting of polyethylene glycol, polypropylene glycol, diglycidyl ether, sorbitol, polyoxyethylene ether of saturated fatty alcohols, and a combination thereof.
7 . The composition of claim 1 , wherein the functional modifier further comprises:
an antioxidant selected from at least one of phosphite and benzofuranone in a range of 0-0.1 weight percentage; and
a lubricating agent in the range of 0-0.5 weight percentage.
8 . The composition of claim 1 , wherein the reinforcing filler has a particle size ranging from 10-50 nm.
9 . The composition of claim 1 , comprising:
the bio-based copolyester in a range of 85-99 weight percentage; and
the functional modifier in a range of 1-15 weight percentage.
10 . The composition of claim 1 , wherein the functional modifier comprises:
the germ-repellent agent in a range of 1-2 weight percentage;
the reinforcing filler in a range of 0-0.1 weight percentage; and
the dispersing agent in a range of 0-0.2 weight percentage.
11 . The composition of claim 1 , wherein the dispersing agent binds to a hydrophobic end of the germ-repellent agent while a hydrophilic end of the germ-repellent agent remains exposed to the bio-based copolyester.
12 . The composition of claim 1 , wherein the germ-repellent composition exhibits a germ-repellent property with more than 90% bacterial adhesion reduction based upon testing with a test protocol with reference to modified ISO 22196: 2011 standard.
13 . The composition of claim 1 , wherein the germ-repellent composition compared with the relative virgin copolyester exhibits a mechanical property with less than 10% reduction, or no reduction based upon testing with a test protocol with reference to ASTM D256 and ASTM D638 standard, wherein the mechanical property is selected from at least one of tensile strength, elongation at break, and Izod impact strength.
14 . The composition of claim 1 , wherein the germ-repellent composition compared with the relative virgin copolyester exhibits:
heat resistance with less than 5 Celsius degrees reduction or no reduction, wherein heat resistance is heat deflection temperature, on testing with ISO 75-test method; and
an optical property than 5% reduction, or no reduction, and the optical property is light transmittance based upon testing in accordance with ASTM D1003-standard test method.
15 . A method for preparing a germ-repellent composition masterbatch, comprising:
providing a bio-based copolyester;
mixing the bio-based copolyester with a functional modifier to obtain a pre-blend, wherein the functional modifier comprises a reinforcing filler, a dispersing agent encapsulating the reinforcing filler, and a germ-repellent agent binding the dispersing agent; and
compounding of the pre-blend via thermal processing to obtain a germ-repellent composition masterbatch.
16 . The method of claim 15 , wherein the thermal processing is selected from the group comprising reactive extrusion, twin-screw extrusion, and internal mixing.
17 . The method of claim 15 , wherein the thermal processing is a twin-screw extrusion performed at,
a temperature ranging from 100-280° C.;
a feeding rate in the range of 7-12%;
a screw speed in the range of 70-120 rpm; and
a torque in the range of 60-70 Nm.
18 . The method of claim 15 , wherein the germ-repellent composition masterbatch comprises the germ-repellent agent having an overall mass percentage of no more than 10% in the masterbatch.
19 . A method for preparing a germ-repellent article, comprising:
providing the germ-repellent composition masterbatch of claim 15 ;
diluting the germ-repellent composition masterbatch with the bio-based copolyester via a thermal processing to form a diluted germ-repellent composition, wherein dilution is carried out at a rate ranging from 1:2-1:10; and
molding the diluted germ-repellent composition in a shape to obtain the germ-repellent article.
20 . The method of claim 19 , wherein the germ-repellent agent in the diluted germ-repellent composition comprises an overall mass percentage of no more than 3% in the masterbatch.