Aqueous polyurethane emulsion for ultra-thin polyurethane condom with low modulus and high strength, and preparation method therefor
AssigneeReckitt Benckiser Health Limited
InventorsWeihu Li, Wenhe Guo, Baoling Zhu, Fei Wang, Jiabing Dai
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Abstract
Provided are a waterborne polyurethane emulsion for ultra-thin polyurethane condoms having a low modulus and a high strength, and a method for preparing the emulsion, wherein the waterborne polyurethane emulsion comprises 15 to 18 parts by mass of a macromolecular diol, 4 to 6 parts by mass of a diisocyanate, 0.6 to 0.9 parts by mass of a hydrophilic chain extender, 0.4 to 0.8 parts by mass of a small-molecule chain extender, and the like. The prepared waterborne polyurethane emulsion is characterized by a low modulus, a high strength, and high resilience.
Claims17
A waterborne polyurethane emulsion, comprising:
- 15 to 18 parts by mass of a macromolecular diol selected from the group consisting of polypropylene glycol (PPG), polytetrahydrofuran ether glycol (PTMEG), poly(neopentyl glycol adipate) (PNA), and combinations thereof,
- 4 to 6 parts by mass of a diisocyanate,
- 0.6 to 0.9 parts by mass of a hydrophilic chain extender,
- 0.4 to 0.8 parts by mass of a small-molecule chain extender selected from the group consisting of cyclohexanedimethanol (CHDM), 1,4-butanediol (BD), methylpropanediol (MPD), and combinations thereof,
- 0.5 to 0.68 parts by mass of a salt-forming agent,
- 0.3 to 0.5 parts by mass of a cross-linking agent,
- 0.1 to 2.0 parts by mass of a modifying agent,
- 50 to 55 parts by mass of an ice-water mixture, and
- 21 to 23 parts by mass of acetone;
- wherein said modifying agent is a polyether substance that causes the terminal groups of the chain of the waterborne polyurethane molecule to form a cross-linked structure.
A method for preparing a waterborne polyurethane emulsion, comprising at least the following steps:
- providing a reactor;
- adding to said reactor 15 to 18 parts by mass of a macromolecular diol selected from the group consisting of polypropylene glycol (PPG), polytetrahydrofuran ether glycol (PTMEG), poly(neopentyl glycol adipate) (PNA), and combinations thereof, 4 to 6 parts by mass of a diisocyanate, 0.6 to 0.9 parts by mass of a hydrophilic chain extender, 0.4 to 0.8 parts by mass of a small-molecule chain extender, 0.5 to 0.68 parts by mass of a salt-forming agent, and 4 to 23 parts by mass of acetone to obtain a prepolymer, and wherein the small-molecule chain extender is selected from the group consisting of cyclohexanedimethanol (CHDM), 1,4-butanediol (BD), methylpropanediol (MPD), and combinations thereof;
- mixing said prepolymer, 0.3 to 0.5 parts by mass of a cross-linking agent, and 50 to 55 parts by mass of an ice-water mixture to obtain an open-chain prepolymer;
- and
- adding 0.1 to 2.0 parts by mass of a modifying agent to said open-chain prepolymer, so that the terminal groups of said open-chain prepolymer form a cross-linked structure to obtain said waterborne polyurethane emulsion, and wherein the modifying agent is a polyether substance.
Dependencies are inferred from the claim text.