TH40974A - The manufacturing process of transparent polyurethane/urea elastomer. - Google Patents

Abstract

DC60 (11/06/42) This invention reveals a process for fabricating transparent elastomers. In the first step, polyols with a narrow molecular weight distribution (Mw/Mn <1.5) are reacted with aromatic diisocyanates with NCO/OH ratios ranging from approximately 1.3 to approximately 3.0 to obtain a prepolymer containing non-viscous terminal isocyanates. A mixture containing this prepolymer and aliphatic diisocyanates is then reacted with aromatic diamines to obtain a transparent elastomer. The elastomers exhibit excellent overall physical and mechanical properties, including elasticity greater than 55%. These elastomers are valuable for grid lining and other applications where transparency is critical. This invention reveals a process for fabricating transparent elastomers. In the first step, polyols (Mw/Mn <1.5) are reacted with aromatic diisocyanates with a narrow molecular weight distribution (NCO/OH ratios ranging from approximately 1.3 to approximately 3.0) to obtain a prepolymer containing non-viscous terminal isocyanates. A non-viscous terminal yanate is obtained, and a mixture containing this prepolymer and aliphatic diisocyanate is then reacted with aromatic diamines to produce a transparent elastomer. This elastomer exhibits excellent overall physical and mechanical properties, including elasticity greater than 55%. These elastomers are valuable for grid scaffolding and other applications where transparency is critical.

Claims (25)

1. The process for manufacturing specific-type polyurethane/urea elastomer consists of: (a) Aromatic diisocyan reaction Yanates and polyols containing polydispersity (Mw/Mn). Less than approximately 1.5 to obtain a prepolymer with... Terminal isocyanates, with a ratio of NCO/OH. In the range of approximately 1.3 to approximately 3.0. (b) Mixing of prepolymer with aliphatic polymer. Diisocyanates are used to obtain a prepolymer mixture. Aliphatic diisocyanates containing NCO3 in... The range is from approximately 2% to about 13% by weight. and (c) Prepolymer mixture reaction/ Aliphatic diisocyanates and aromatic diamines In the quantity and by effective methods to achieve it. Clear polyurethane/urea elastomer 2. The process pursuant to claim 1 by aromatic diide. Socyanates were selected from a group that included toluene. Isocyanates and MDI containing other MDI isomers. Above 4.4''-MDI by at least 15% by weight. 3. Process according to claim 1 by aromatic diide. Socyanates contain less than 90% 4,''4-MDI. weight 4. The process pursuant to claim 1 involves polyols containing Mw/Mn. Less than approximately 1.4 5. The process under Claim 1 by Polyol. The Mw/Mn ratio is less than approximately 1.2. 6. The process under Claim 1, where polyols are involved. The unsaturated fatty acid content is less than approximately 0.02 milliequivalents/g. 7. The process under Claim 1, by polyol, has... The unsaturated fatty acid content is less than approximately 0.01 milliequivalents/g. 8. The process under claim 1, where polyols have weight. Equivalents range from approximately 750 to approximately... 10,000 9. The process under claim 1 involves the use of prepolymers. Prepared with an NCO/OH ratio ranging from approximately... 1.5 to approximately 2.0 10. The process according to claim 1, where the prepolymer is... Prepare for an NCO/OH ratio in the range of approximately... 1.5 to approximately 1.8 11. Process according to Claim 1 by prepolymer mixture. Mer/aliphatic diisocyanate has lower viscosity. Approximately 5000 cps at 80°C. 12. Process according to Claim 1 by prepolymer mixture. Mer/aliphatic diisocyanate has lower viscosity than... Approximately 3000 cps at 80°C. 13. Procedure under Claim 1 by Aliphatic Die Socyanates were selected from the group consisting of hydrochlorides. Genetically MDI, isofarone didisocyanate, tetracycline Methylxylene diisocyanate (TMXDI) and a mixture of... The substance 14. The process according to claim 1, by quantity of NCO of... The prepolymer/aliphatic diisocyanate mixture is in the range of... From approximately 3% to approximately 10% by weight. 15. The process under claim 1 by aromatic diamines. Selected from a group consisting of diethyltoluene diethyltoluene. DETDA, dimethylthiotoluene diamine (DMTTDA) And a mixture of those substances. 16. Process according to claim 1 by aromatic diamines. The ratio of NCO₂/NH₃ used ranges from approximately 0.9 to... Approximately 1.2 17. The process under claim 1 by aromatic dioxide. Amines have a Gardner coloration of approximately 7 or less. 18. The process under claim 1 by aromatic dye. Amines have a Gardner staining value of approximately 3 or less. 19. Procedure according to Claim 1 by reaction in the first step. Episode (c) has a potlife of at least approximately 20 seconds. 20. Procedures under Claim 1 by elastomer. The products manufactured have a Shore hardness of at least approximately 75A. 21. Claim process 1 by elastomer. The products manufactured have at least approximately 55% flexibility. 22. The process pursuant to claim 1 by elastomer. The products manufactured have at least approximately 65% flexibility. 23. The process pursuant to claim 1, which consists of: (a) Reaction of aromatic diisocyanate with poly Ether diol with a polydispersivity (Mw/Mn) less than approximately 1.2 To obtain a prepolymer with terminal isovianate. The NCO/OH ratio ranges from approximately 1.5. To about 1.8 (b) Mixing of prepolymer with aliphatic diisocyanate Selected from a group that included hydrogenated MDI, Isophorone diisocyanate, tetramethylxylene Diisocyanate (TMXDI) and a mixture of the following substances. In other words, to obtain a prepolymer/aliphatic mixture. Isocyanates with NCO3 content in the range of approximately... 3 to approximately 10% by weight. (c) Prepolymer/diisocycle reaction Yanates and aromatic diamines selected from a group consisting of... With diethyltoluene diamine (DETDA), dimethylthiotoluene Dimethicone (DMTTDA) and a mixture of the aforementioned ingredients in the following quantities: And effective methods for producing polyurethane elastomer. Clear tomer 24. Polyurethane/urea elastomer produced by process In the event of any one of the aforementioned claims. 25. Skateboard wheels arranged in a row, or a skateboard made of elastic. Tomer in claim 24. (25 claims, drawing - image)