High-light-transmittance and high-weather-resistance thermoplastic polyurethane elastomer

Abstract

The invention provides a thermoplastic polyurethane elastomer with high light transmittance and high weather resistance, the thermoplastic polyurethane elastomer comprises reactants obtained by aliphatic polyisocyanate, polymer polyol and a chain extender, the polymer polyol comprises polycarbonate polyol PCDL, and the chain extender comprises polycarbonate polyol PCDL; the aliphatic polyisocyanate comprises dicyclohexylmethane H12MDI and other types of aliphatic polyisocyanate, the chain extender comprises micromolecular dihydric alcohol, and the micromolecular dihydric alcohol comprises a mixture of cyclic structure micromolecular dihydric alcohol and non-cyclic structure micromolecular dihydric alcohol; the high-light-transmittance and high-weather-resistance thermoplastic polyurethane elastomer is good in mechanical property and yellowing resistance, the transparency is obviously higher than that of conventional thermoplastic polyurethane, when the high-light-transmittance and high-weather-resistance thermoplastic polyurethane elastomer is applied to a safety glass laminated material, the cohesiveness of the thermoplastic polyurethane material and glass is excellent, and obvious yellowing and deterioration phenomena do not occur even if the thermoplastic polyurethane elastomer is used outdoors for a long time.

Description

Technical Field

[0001] The invention relates to a thermoplastic polyurethane elastomer, in particular to a thermoplastic polyurethane elastomer with high light transmittance and high weather resistance and application thereof. Background Art

[0002] Thermoplastic polyurethane (TPU) elastomer is a new type of organic polymer synthetic material with great potential. Its unique block linear molecular structure and structural designability give TPU excellent tensile properties, resilience, aging resistance and weather resistance. Therefore, TPU can be widely used in many fields such as footwear and clothing, medical and health care, electronic devices, wires and cables, and automotive parts.

[0003] In the fields of construction and transportation, especially in special occasions with high safety requirements such as automobiles, airplanes, high-speed railways, warships, and doors and windows of special buildings on high-rise building walls, the impact resistance and safety of safety glass are crucial. Laminated glass has been successfully used in high-speed railway windshields, Tesla skylight glass, military ship command tower glass windows, armored vehicle glass windows and other fields due to its best impact resistance and high safety even if it is broken. Laminated glass is a flat or curved composite glass product made by hot-pressing two or more pieces of flat glass with transparent resin sheets. The resin interlayer bonded in the middle prevents the glass from splashing when it is broken by impact, producing radial cracks and not hurting people. Therefore, the impact strength of the product is much higher than that of ordinary glass. In addition, by using different glass sheets and interlayer materials, light resistance, heat resistance, moisture resistance, cold resistance and other characteristics can also be obtained. The quality of laminated glass mainly depends on the strength, transparency, weather resistance, moisture resistance and glass bonding strength of the resin interlayer. Aliphatic TPU is an ideal material for laminated glass interlayer due to its excellent yellowing resistance, moisture resistance, high strength and excellent glass bonding performance. Summary of the invention

[0004] Technical problem: The purpose of the present invention is to provide a thermoplastic polyurethane elastomer with high light transmittance and high weather resistance, and to utilize the modified thermoplastic polyurethane elastomer for application in the field of glass interlayer materials.

[0005] Technical solution: The present invention provides a high-transmittance and high-weather-resistant thermoplastic polyurethane elastomer, comprising a reactant obtained from an aliphatic polyisocyanate, a polymer polyol, and a chain extender, wherein the polymer polyol comprises a polycarbonate polyol PCDL.

[0006] The polymer polyols include polycarbonate polyol PCDL and other types of polymer polyols; the mass ratio of the polycarbonate polyol PCDL to other types of polymer polyols is 1:0.1 to 1:0.8.

[0007] The other types of polymer polyols include polyether polyols, and the polyether polyols include at least one of polytetramethylene ether polyol PTMEG, polyoxypropylene polyol PPG, polyoxyethylene polyol PEG, and polyoxyethylene-propylene polyol P (EG-PG). Preferably, the polyether polyol is preferably polytetramethylene ether polyol PTMEG.

[0008] The number average molecular weight of the polycarbonate polyol PCDL is 1000-4000 g / mol, and the number average molecular weight of the polyether polyol is 1000-2500 g / mol.

[0009] The aliphatic polyisocyanate includes dicyclohexylmethane H12MDI and other types of aliphatic polyisocyanates. The other types of aliphatic polyisocyanates include at least one of dicyclohexylmethane diisocyanate IPDI and hexamethylene diisocyanate HDI. Preferably, the other types of aliphatic polyisocyanates include isophorone diisocyanate IPDI.

[0010] The mass ratio of the dicyclohexylmethane H12MDI to other types of aliphatic polyisocyanates is 1:0.02 to 1:0.7.

[0011] The chain extender comprises small molecule diols, and the small molecule diols comprise a mixture of cyclic small molecule diols and non-cyclic small molecule diols.

[0012] The non-cyclic small molecule diol includes one or more of ethylene glycol EG, propylene glycol PG, butanediol BDO, pentanediol PD, neopentyl glycol NPG, and hexanediol HG; the non-cyclic small molecule diol accounts for 50-90% of the total mass of the chain extender, preferably 65-85%; the cyclic small molecule diol includes one or more of 1,2-cyclobutane dimethanol, 1,3-cyclobutane dimethanol, and 1,4-cyclohexanedimethanol.

[0013] The high light transmittance and high weather resistance thermoplastic polyurethane elastomer is obtained by reacting the following raw materials in parts by weight:

[0014] 30-45 parts by weight of aliphatic polyisocyanate;

[0015] 35-65 parts by weight of polymer polyol;

[0016] 5 to 15 parts by weight of chain extender;

[0017] The isocyanate index is 0.95:1 to 1.05:1; the isocyanate index is the molar ratio of the NCO group in the polyisocyanate to the group reactive to NCO in the polymer polyol, the chain extender and the end-capping agent.

[0018] The high-transmittance and high-weather-resistant thermoplastic polyurethane elastomer also contains at least one of an antioxidant and an ultraviolet light absorber; the antioxidant includes one or more of antioxidant 168, antioxidant 1010, antioxidant 1024, antioxidant 264, and antioxidant 245, and the added amount of the antioxidant is 0 to 5wt%, calculated based on the total mass of the thermoplastic polyurethane elastomer; the ultraviolet light absorber includes one or more of R-455, UV-329, UV-531, UV-326, and UV-328, and the added amount of the ultraviolet light absorber is 0 to 5wt%, calculated based on the total mass of the thermoplastic polyurethane elastomer.

[0019] Beneficial effects: The high-transmittance and high-weather-resistant thermoplastic polyurethane elastomer of the present invention not only has excellent mechanical properties and good yellowing resistance, but also has significantly higher transparency than conventional thermoplastic polyurethane. When used in safety glass interlayer materials, the thermoplastic polyurethane material has excellent adhesion to glass and does not show obvious yellowing or deterioration even after long-term outdoor use. DETAILED DESCRIPTION

[0020] The invention provides a high-light-transmittance and high-weather-resistant thermoplastic polyurethane elastomer, which is modified and processed to be applied in the field of glass interlayer materials.

[0021] The high-transmittance and high-weatherability thermoplastic polyurethane elastomer provided by the present invention comprises aliphatic polyisocyanate, polymer polyol, and a reactant obtained by a chain extender, wherein the polymer polyol comprises polycarbonate polyol PCDL;

[0022] Furthermore, the polymer polyol includes polycarbonate polyol PCDL and other types of polymer polyols;

[0023] The other types of polymer polyols include polyether polyols, and the polyether polyols include at least one of polytetramethylene ether polyol PTMEG, polyoxypropylene polyol PPG, polyoxyethylene polyol PEG, and polyoxyethylene-propylene polyol P (EG-PG). Furthermore, the polyether polyol is preferably polytetramethylene ether polyol PTMEG;

[0024] The mass ratio of the PCDL to other types of polymer polyols is 1:0.1 to 1:0.8;

[0025] Furthermore, the mass ratio of the PCDL to other types of polymer polyols is 1:0.2 to 1:0.6;

[0026] The number average molecular weight of the PCDL is 1000-3000 g / mol, and the number average molecular weight of the polyether polyol is 1000-2500 g / mol;

[0027] In some embodiments of the invention, the polymer polyol comprises PCDL and PTMEG in a mass ratio of 1:0.2 to 1:0.6;

[0028] The aliphatic polyisocyanate includes dicyclohexylmethane H12MDI and other types of aliphatic polyisocyanates, and the other types of aliphatic polyisocyanates include at least one of dicyclohexylmethane diisocyanate IPDI and hexamethylene diisocyanate HDI;

[0029] Preferably, the other types of aliphatic polyisocyanates include dicyclohexylmethane diisocyanate IPDI;

[0030] Preferably, the mass ratio of the H12MDI to other types of aliphatic polyisocyanates is 1:0.03 to 1:0.7;

[0031] In some embodiments of the invention, the aliphatic polyisocyanate comprises H12MDI and IPDI in a mass ratio of 1:0.03 to 1:0.7;

[0032] The chain extender includes a small molecule diol, and further, the small molecule diol contains a cyclic structure, and further, includes a mixture of a non-cyclic structure small molecule diol and a cyclic structure small molecule diol;

[0033] The non-cyclic small molecule diols include one or more of ethylene glycol EG, propylene glycol PG, butanediol BDO, pentanediol PD, neopentyl glycol NPG, and hexanediol HG;

[0034] The cyclic structure small molecule diol includes one or more of 1,2-cyclobutane dimethanol, 1,3-cyclobutane dimethanol, and 1,4-cyclohexanedimethanol;

[0035] The non-cyclic small molecule diol accounts for 50-90% of the total mass of the chain extender, preferably 65-85%;

[0036] Furthermore, the high light transmittance and high weather resistance thermoplastic polyurethane elastomer is obtained by reacting the following raw materials in parts by weight:

[0037] 30-45 parts by weight of aliphatic polyisocyanate;

[0038] 40-65 parts by weight of polymer polyol;

[0039] Chain extender 7-15 parts by weight;

[0040] Furthermore, the isocyanate index of the high-transmittance and high-weatherability thermoplastic polyurethane elastomer is 0.97:1 to 1.03:1;

[0041] The isocyanate index is the molar ratio of the NCO groups in the polyisocyanate to the groups reactive to NCO in the polymer polyol, chain extender and end-capping agent.

[0042] The high light transmittance and high weather resistance thermoplastic polyurethane elastomer further contains at least one of an antioxidant and an ultraviolet light absorber;

[0043] The antioxidant includes one or more of antioxidant 168, antioxidant 1010, antioxidant 1024, antioxidant 264, and antioxidant 245; the added amount of the antioxidant is 0 to 5 wt%, calculated based on the total mass of the thermoplastic polyurethane elastomer;

[0044] The ultraviolet light absorber includes one or more of R-455, UV-329, UV-531, UV-326, and UV-328; the added amount of the ultraviolet light absorber is 0 to 5 wt%, calculated based on the total mass of the thermoplastic polyurethane elastomer.

[0045] The high-transmittance and high-weather-resistant thermoplastic polyurethane elastomer is prepared by a mixed reaction of aliphatic polyisocyanate, polymer polyol and chain extender;

[0046] The reaction equipment is not particularly limited, as long as the various raw materials can be fully mixed or reacted, for example, one or more selected from a screw extruder, an internal mixer, a stirring kettle, and a casting machine;

[0047] Furthermore, the high-transmittance and high-weatherability thermoplastic polyurethane elastomer is prepared in the presence of a protective gas, which does not participate in the reaction, for example, nitrogen or helium;

[0048] Furthermore, a catalyst commonly used in the art may be added during the mixed reaction process to accelerate the reaction rate; this includes one or more of an organic tin catalyst, an organic titanium catalyst, and an organic bismuth catalyst.

[0049] In some embodiments of the present invention, the high-transmittance and high-weatherability thermoplastic polyurethane elastomer is prepared by a twin-screw extruder, and the steps include:

[0050] The insulation temperature of aliphatic polyisocyanate is 40-80°C, the insulation temperature of polymer polyol is 90-130°C, and the insulation temperature of chain extender is 40-80°C to ensure that the raw materials are in liquid state;

[0051] The heat-insulated polyisocyanate, polymer polyol and chain extender are added to the front-end twin-screw extruder through a mixing system for mixing and reaction, the temperature of the screw is controlled to be 140-180° C., and the obtained polymer melt is pelletized underwater and dried;

[0052] Preferably, the catalyst is selectively added to the front section of the twin screw and mixed with the raw materials, and the antioxidant, ultraviolet light absorber, and lubricant are selectively added to the rear section of the twin screw and mixed with the molten thermoplastic polyurethane elastomer. The prepared thermoplastic polyurethane elastomer particles and other materials can also be melted and mixed again in the mixer;

[0053] Preferably, other additives in the art can be further added to the high light transmittance and high weather resistance thermoplastic polyurethane elastomer according to demand to improve the performance of the thermoplastic polyurethane elastomer.

[0054] The principles and features of the present invention are described below in conjunction with examples. The examples are only used to explain the present invention and are not used to limit the scope of the present invention.

[0055] The high light transmittance and high weather resistance thermoplastic polyurethane elastomers of the embodiments and comparative examples are obtained by reacting 1 part by weight of the raw materials shown in the following table:

[0056] Table 1:

[0057]

[0058]

[0059] In the above-mentioned embodiments and comparative examples, a twin-screw extruder is used to prepare the high-transmittance and high-weather-resistant thermoplastic polyurethane elastomer, and the steps include:

[0060] According to the weight parts of Table 1, the above-mentioned heat-insulated polyisocyanate, polymer polyol and chain extender are added into the front section of the twin-screw extruder through a mixing system for mixing and reaction, and the temperature of the screw is controlled to be 140-180° C. The obtained polymer melt is pelletized underwater and dried to obtain;

[0061] 0.2 parts by weight of stannous octoate catalyst was added to the front section of the twin screw and mixed with the raw materials. Antioxidants, ultraviolet light absorbers, light stabilizers and other additives listed in Table 2 were added to the rear section of the twin screw and mixed with the molten thermoplastic polyurethane elastomer, and then dried by underwater pelletizing.

[0062] Table 2:

[0063]

[0064] The thermoplastic polyurethane elastomers prepared in the examples and comparative examples were subjected to the following performance tests:

[0065] Hardness: ASTM D2240;

[0066] Tensile strength: ASTM D412;

[0067] Haze: ASTM D1003;

[0068] Glass bonding grade: Put the TPU film between two pieces of 200mm×200mm glass in a vacuum at 125℃, freeze it at -20℃ for 2 hours, and gently knock 50% of the glass on the inclined surface with a 0.5kg hammer until the glass breaks, then knock on the other side to check the percentage of the area of ​​the film leaking out of both sides to the knocked surface. The glass bonding grade of 10 means no film leaking out, 0 means all peeling off, and the smaller the number, the lower the bonding grade;

[0069] Yellowing resistance: dE is tested after 100 hours of xenon lamp aging.

[0070] The performance data results are shown in Table 3 below:

[0071] Table 3:

[0072]

Claims

1. A high light transmittance and high weather resistance thermoplastic polyurethane elastomer, characterized in that: The invention comprises reactants obtained from aliphatic polyisocyanate, polymer polyol and chain extender, wherein the polymer polyol comprises polycarbonate polyol PCDL.

2. The high light transmittance and high weather resistance thermoplastic polyurethane elastomer according to claim 1, characterized in that: The polymer polyols include polycarbonate polyol PCDL and other types of polymer polyols; the mass ratio of the polycarbonate polyol PCDL to other types of polymer polyols is 1:0.1 to 1:0.

8.

3. The high light transmittance and high weather resistance thermoplastic polyurethane elastomer according to claim 2, characterized in that: The other types of polymer polyols include polyether polyols, and the polyether polyols include at least one of polytetramethylene ether polyol PTMEG, polyoxypropylene polyol PPG, polyoxyethylene polyol PEG, and polyoxyethylene-propylene polyol P (EG-PG). Preferably, the polyether polyol is preferably polytetramethylene ether polyol PTMEG.

4. The high light transmittance and high weather resistance thermoplastic polyurethane elastomer according to claim 3, characterized in that: The number average molecular weight of the polycarbonate polyol PCDL is 1000-4000 g / mol, and the number average molecular weight of the polyether polyol is 1000-2500 g / mol.

5. The high light transmittance and high weather resistance thermoplastic polyurethane elastomer according to claim 1, characterized in that: The aliphatic polyisocyanate includes dicyclohexylmethane H12MDI and other types of aliphatic polyisocyanates. The other types of aliphatic polyisocyanates include at least one of dicyclohexylmethane diisocyanate IPDI and hexamethylene diisocyanate HDI. Preferably, the other types of aliphatic polyisocyanates include isophorone diisocyanate IPDI.

6. The high light transmittance and high weather resistance thermoplastic polyurethane elastomer according to claim 5, characterized in that: The mass ratio of the dicyclohexylmethane H12MDI to other types of aliphatic polyisocyanates is 1:0.02 to 1:0.

7.

7. The high light transmittance and high weather resistance thermoplastic polyurethane elastomer according to claim 1, characterized in that: The chain extender comprises a small molecule diol, and the small molecule diol comprises a mixture of a cyclic structure small molecule diol and a non-cyclic structure small molecule diol.

8. The high light transmittance and high weather resistance thermoplastic polyurethane elastomer according to claim 7, characterized in that: The non-cyclic small molecule diol includes one or more of ethylene glycol EG, propylene glycol PG, butanediol BDO, pentanediol PD, neopentyl glycol NPG, and hexanediol HG; the non-cyclic small molecule diol accounts for 50-90% of the total mass of the chain extender, preferably 65-85%; the cyclic small molecule diol includes one or more of 1,2-cyclobutane dimethanol, 1,3-cyclobutane dimethanol, and 1,4-cyclohexanedimethanol.

9. The high light transmittance and high weather resistance thermoplastic polyurethane elastomer according to claim 1, characterized in that: The high light transmittance and high weather resistance thermoplastic polyurethane elastomer is obtained by reacting the following raw materials in parts by weight: 30-45 parts by weight of aliphatic polyisocyanate; 35-65 parts by weight of polymer polyol; 5 to 15 parts by weight of chain extender; The isocyanate index is 0.95:1 to 1.05:1; the isocyanate index is the molar ratio of the NCO group in the polyisocyanate to the group reactive to NCO in the polymer polyol, the chain extender and the end-capping agent.

10. The high light transmittance and high weather resistance thermoplastic polyurethane elastomer according to claim 1, characterized in that: The high-transmittance and high-weather-resistant thermoplastic polyurethane elastomer also contains at least one of an antioxidant and an ultraviolet light absorber; the antioxidant includes one or more of antioxidant 168, antioxidant 1010, antioxidant 1024, antioxidant 264, and antioxidant 245, and the added amount of the antioxidant is 0 to 5wt%, calculated based on the total mass of the thermoplastic polyurethane elastomer; the ultraviolet light absorber includes one or more of R-455, UV-329, UV-531, UV-326, and UV-328, and the added amount of the ultraviolet light absorber is 0 to 5wt%, calculated based on the total mass of the thermoplastic polyurethane elastomer.

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