Acrylpimarinol modified thermoplastic polyurethane and preparation method thereof

Abstract

The invention discloses acrylpimaric alcohol modified thermoplastic polyurethane and a preparation method thereof, the acrylpimaric alcohol modified thermoplastic polyurethane comprises the following components in parts by weight: 5-50 parts of acrylpimaric alcohol, 0-75 parts of polyol, 0-25 parts of a chain extender, 10-55 parts of diisocyanate and 0.001-0.1 part of a catalyst, and the chain extender is not 0. According to the acrylpimaric alcohol modified thermoplastic polyurethane provided by the invention, a rosin ternary phenanthrene ring structure is introduced into a linear main chain structure of thermoplastic polyurethane through reaction of dihydric alcohol of acrylpimaric alcohol and diisocyanate; compared with a traditional carbon chain structure, the rosin resin not only retains rigid structural characteristics of rosin, but also retains good flexibility of a fat six-membered ring non-planar structure, so that a prepared coating film has excellent comprehensive properties such as good gloss, high hardness, strong adhesive force, hydrophobicity and corrosion resistance compared with a traditional thermoplastic polyurethane material.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane materials, and in particular to propylene pinamarin modified thermoplastic polyurethane and a preparation method thereof. Background Art

[0002] Thermoplastic polyurethane elastomer (TPU) is a type of plasticizable and soluble polyurethane elastomer with high modulus, high strength, high elongation and high elasticity, excellent wear resistance, oil resistance, low temperature resistance, aging resistance, and better biocompatibility and biostability. The medical device industry currently has a huge demand for medical-grade thermoplastic polyurethane elastomers, which is increasing year by year and may gradually replace polyvinyl chloride as the main material for the production of medical catheters.

[0003] Currently, commercial thermoplastic polyurethane elastomers are mainly composed of three components: isocyanate, polyol and chain extender, and the raw materials are all derived from fossil resources. However, with the continuous depletion of oil resources, it is imperative to find new renewable raw materials. The currently developed bio-based polyurethanes mainly include plant oil-based polyurethanes, polysaccharide-based polyurethanes, rosin-based polyurethanes, etc.

[0004] Patent CN109438653 discloses a method for preparing a bio-based thermoplastic polyurethane elastomer by preparing polyester polyols with bio-based acids such as succinic acid, sebacic acid, and polylactic acid, bio-based alcohols, and bio-based 1,3-propylene glycol, bio-based 1,2-propylene glycol, bio-based ethylene glycol, and bio-based 1,4-butanediol. However, the reaction temperature of the obtained polyurethane is too high, which is not conducive to the simplification of the production process and the improvement of production efficiency. Patent CN117866414 discloses a method for preparing polyurethane using polypropylene carbonate polyol, bio-based 1,4-butanediol, and 4,4-diphenylmethane diisocyanate, and adding a biodegradation accelerator, an antioxidant, and a plasticizer to obtain a method for preparing a high bio-based composite material. The material has a good biodegradation rate, but the mechanical properties, especially the hardness, are not excellent enough.

[0005] Therefore, it is very meaningful to provide a method for preparing thermoplastic polyurethane with low cost. Summary of the invention

[0006] In view of this, the present invention provides an propylene pinamarin modified thermoplastic polyurethane and a preparation method thereof, so as to improve the mechanical properties of polyurethane on the basis of reducing production costs.

[0007] The technical solution of the present invention comprises: an propylene pinomacinol modified thermoplastic polyurethane, which comprises, by weight: 5-50wt% of propylene pinomacinol, 0-75wt% of polyol, 0-25wt% of chain extender, 10-55wt% of diisocyanate, and 0.001-0.1wt% of catalyst, wherein the chain extender is not 0.

[0008] Preferably, in terms of mass percentage, the total content of bio-based components in acrylpimarol, polyol and chain extender is greater than or equal to 50wt%.

[0009] Preferably, the polyol has a hydroxyl value ranging from 18 to 140 mg KOH / g; a moisture content less than or equal to 300 ppm, and an acid value less than or equal to 2 mg;

[0010] In terms of mass percentage, the polyol comprises 50-100 wt % of bio-based polyester polyol and 0-50 wt % of petroleum-based polyol;

[0011] The bio-based content of the bio-based polyester polyol is greater than or equal to 50 wt%.

[0012] Preferably, the catalyst comprises one of a non-tin environmentally friendly catalyst or a tin-containing catalyst; the catalyst content is less than or equal to 400 ppm;

[0013] The organotin catalyst is one of stannous octoate, dibutyltin dilaurate, dibutyltin dioxalate, and dibutyltin didodecylsulfide;

[0014] The non-tin environmentally friendly catalyst is one of triethylamine, triethylenediamine, dimethylcyclohexylamine, dimethylcyclohexylamine of tertiary amines, potassium isooctanoate, potassium oleate, bismuth isooctanoate and zinc isooctanoate of organic metals.

[0015] In a second aspect, the present invention further provides a method for preparing the above-mentioned propylene pinamarin modified thermoplastic polyurethane, comprising the following steps:

[0016] Step 1: blending propylene pinamarin, polyol and chain extender, adding solvent thereto, and mixing evenly to obtain a mixed solution A;

[0017] Step 2: adding diisocyanate and catalyst to the mixed solution A in sequence, stirring evenly and reacting at 60-200° C., and removing the solvent after the reaction to obtain propylene pinamarin modified thermoplastic polyurethane;

[0018] The solvent is one or more of xylene, ethyl acetate, butyl acetate, dichloromethane, tetrahydrofuran, and toluene;

[0019] Or, comprising the steps of:

[0020] Propylene pimaric alcohol, polyol, chain extender, diisocyanate and catalyst are mixed and extruded through industrial twin-screw reaction to obtain thermoplastic polyurethane modified with propylene pimaric alcohol.

[0021] Preferably, the preparation method of propylene pimaric acid is as follows: dissolving propylene pimaric acid in a solvent, slowly adding a reducing agent under low temperature conditions and under the protection of an inert gas, reacting for 0.5 to 6 hours, and then heating to 40 to 80° C. and reacting for 6 to 24 hours;

[0022] After the reaction is completed, the excess reducing agent is quenched with a quenching agent, deionized water is added and fully shaken, filtered, and vacuum filtered at 40-60°C until constant weight is reached;

[0023] Add a non-water-soluble solvent to the constant-weight filtrate, shake it thoroughly, let it stand to separate the layers, remove the water layer, and perform high-vacuum rotary evaporation on the oil layer liquid to obtain a viscous liquid product having a diol structure - propylene pinamarin;

[0024] The solvent is one or more mixed solvents selected from anhydrous tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, ethyl ether, ethyl butyl ether, dihexyl ether, dipentyl ether, and 3-methylfuran;

[0025] The reducing agent is one or more mixtures of lithium aluminum hydride, sodium borohydride, potassium borohydride or dibutylaluminum hydride;

[0026] The quenching agent is one or more of water, sodium hydroxide aqueous solution, sodium carbonate aqueous solution, sodium bicarbonate aqueous solution, hydrochloric acid solution or disulfuric acid solution;

[0027] The non-aqueous solvent is a mixture of one or more of toluene, xylene, ethyl acetate, and butyl acetate;

[0028] The low temperature condition is -10°C to 15°C, and the inert gas is preferably nitrogen or argon, or a mixture of the two.

[0029] The present invention provides an propylene pinmarol modified thermoplastic polyurethane and a preparation method thereof. Compared with the existing thermoplastic polyurethane, the present invention uses bio-based material rosin as a raw material to replace traditional petroleum-based raw materials, and has the characteristics of being green and environmentally friendly. In addition, the propylene pinmarol modified thermoplastic polyurethane provided by the present invention introduces the rosin three-membered phenanthrene ring structure into the linear main chain structure of the thermoplastic polyurethane through the reaction of the diol of propylene pinmarol with diisocyanate, and retains the rigid structural characteristics of the rosin and the good flexibility of the aliphatic six-membered ring non-planar structure compared with the traditional carbon chain structure. Therefore, the coating film prepared by the coating has good gloss, high hardness, strong adhesion, and excellent comprehensive properties such as hydrophobicity and anticorrosion compared with the traditional thermoplastic polyurethane material.

[0030] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 This is a schematic diagram of the reaction process for preparing an propylene pinamatan-modified thermoplastic polyurethane provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0034] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of methods consistent with some aspects of the present invention as detailed in the appended claims.

[0035] In the first aspect, this embodiment provides an propylene pinomacinol-modified thermoplastic polyurethane, which is specifically polymerized from the following components: propylene pinomacinol, polyol, chain extender, diisocyanate, catalyst, by mass:

[0036] The propylene pinacol component is 5 to 50 parts, preferably 6 to 26 parts; the polyol component is 0 to 75 parts, preferably 24-75 parts; the chain extender component is 0 to 25 parts, preferably 1.5 to 23 parts; the diisocyanate component is 10 to 55 parts, preferably 12 to 34 parts; the catalyst component is 0.001 to 0.1 parts, preferably 0.01 to 0.05 parts.

[0037] The total content of bio-based components in the acrylpimarol component, the polyol component, and the chain extender component is greater than or equal to 50wt%, preferably greater than or equal to 60wt%. In this embodiment, bio-based refers to biological origin, and petroleum-based refers to petroleum origin. Here, the content of bio-based components refers to the percentage of the total mass of biologically derived components in the total components.

[0038] a: The preparation method of propylene pimaric acid is as follows: dissolve propylene pimaric acid in solvent 1, and slowly add a reducing agent under low temperature conditions under the protection of inert gas, react for 0.5 to 6 hours after the reducing agent is added, and then heat to 40 to 80°C to react for 6 to 24 hours. After the reaction is completed, the excess reducing agent is quenched with a quenching agent, and then deionized water is added and fully shaken, filtered, and vacuum filtered at 40 to 60°C to constant weight. A non-aqueous solvent is added to the constant weight filtrate, and after sufficient shaking, the stratification is allowed to stand, the water layer is removed, and the oil-containing layer liquid is subjected to high vacuum rotary evaporation to obtain a viscous liquid product having a diol structure-propylene pimaric acid.

[0039] The solvent 1 is preferably a mixed solvent of one or more of anhydrous tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethyl ether, ethyl butyl ether, dihexyl ether, dipentyl ether, and 3-methylfuran.

[0040] The low temperature condition can be achieved by a liquid nitrogen quick freezing method, or by maintaining a temperature condition of -10°C to 15°C through a temperature control device.

[0041] The inert gas is preferably nitrogen or argon, or a mixture of the two.

[0042] The reducing agent is preferably one or more of lithium aluminum hydride, sodium borohydride, potassium borohydride or dibutylaluminum hydride.

[0043] The quenching agent is one or more of water, sodium hydroxide aqueous solution, sodium carbonate aqueous solution, sodium bicarbonate aqueous solution, hydrochloric acid solution or diethyl sulfuric acid solution.

[0044] The non-aqueous solvent is preferably a mixture of one or more of toluene, xylene, ethyl acetate and butyl acetate.

[0045] b: The number average molecular weight of the polyol is 800-6000 g / mol, preferably 1000-4000 g / mol, based on the total weight of the polyol component, the polyol comprises 50-100 wt% of bio-based polyester polyol and 0-50 wt% of petroleum-based polyol, wherein 70-100 wt% of bio-based polyester polyol and 0-30 wt% of petroleum-based polyol are preferred;

[0046] The polyol has a hydroxyl value ranging from 18 to 140 mg KOH / g; a moisture content of less than or equal to 300 ppm, preferably less than or equal to 200 ppm; and a catalyst content of less than or equal to 400 ppm, preferably less than or equal to 200 ppm.

[0047] The petroleum-based polyol includes one or more of petroleum-based 1,3-propylene glycol, ethylene glycol, 1,2-propylene glycol, 1,4-butylene glycol, dipropylene glycol, hexylene glycol, diethylene glycol, methyl propanediol, neopentyl glycol, and petroleum-based polyester polyols. Among them, petroleum-based polyester polyols are preferred, specifically one or more of polybutylene adipate diol (PBA), polyethylene adipate diol (PEA), and polyhexamethylene adipate diol (PHA).

[0048] The bio-based polyester polyol is obtained by reacting a bio-based acid with one or more small molecule alcohols, and the small molecule alcohols can be bio-based or petroleum-based or both. The bio-based acid is mainly one or more of bio-based succinic acid, sebacic acid, and polylactic acid. The bio-based small molecule alcohol is mainly one or more of bio-based 1,3-propylene glycol, bio-based 1,2-propylene glycol, bio-based ethylene glycol, and bio-based 1,4-butanediol. The petroleum-based small molecule alcohol is one or more of petroleum-based 1,3-propylene glycol, ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, dipropylene glycol, hexanediol, diethylene glycol, methyl propanediol, and neopentyl glycol.

[0049] The bio-based polyester polyol has a hydroxyl value ranging from 18 to 140 mg KOH / g, preferably 28 to 115 mg KOH / g; an acid value less than or equal to 2 mg KOH / g, preferably less than or equal to 1 mg KOH / g; a moisture content less than or equal to 300 ppm, preferably less than or equal to 200 ppm; a catalyst content less than or equal to 400 ppm, preferably less than or equal to 200 ppm; and a biobased content greater than or equal to 50 wt%, preferably greater than or equal to 60 wt%, based on the total weight of the bio-based polyester polyol component.

[0050] The bio-based polyester polyol is preferably one or more of poly(propylene succinate) diol (PPSu), poly(butylene succinate) diol (PBSu), poly(propylene sebacate) diol (PPSe), and poly(butylene sebacate) diol (PBSe).

[0051] c: The chain extender contains 50-100wt% of bio-based chain extender and 0-50wt% of petroleum-based chain extender, preferably 70-100wt% of bio-based chain extender and 0-30wt% of petroleum-based chain extender;

[0052] The petroleum-based chain extender is one or a mixture of petroleum-based ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,4-butanediol, dipropylene glycol, hexanediol, diethylene glycol, methyl propylene glycol, and neopentyl glycol. Petroleum-based 1,4-butanediol is preferred.

[0053] The bio-based chain extender is one or a mixture of bio-based 1,3-propylene glycol, bio-based 1,2-propylene glycol, bio-based ethylene glycol, and bio-based 1,4-butanediol, preferably bio-based 1,3-propylene glycol.

[0054] d: The diisocyanate contains 10-60 wt% of bio-based diisocyanate and 40-90 wt% of petroleum-based diisocyanate, wherein 30-60 wt% of bio-based diisocyanate and 40-70% of petroleum-based diisocyanate are preferred;

[0055] The bio-based diisocyanate is one of bio-based 1,4-butanediisocyanate and bio-based 1,5-pentanediisocyanate, or a mixture of the two.

[0056] Furthermore, the petroleum-based diisocyanate is a mixture of one or more of hexamethylene diisocyanate, 4,4-diphenylmethane diisocyanate, 4,4-dicyclohexylmethane diisocyanate, toluene diisocyanate, isophorone diisocyanate, m-xylylene diisocyanate, and 1,5-naphthalene diisocyanate, preferably 4,4-diphenylmethane diisocyanate and hexamethylene diisocyanate.

[0057] e: The catalyst is preferably 50-100wt% of a non-tin environmentally friendly catalyst and 0-50wt% of a tin-containing catalyst.

[0058] Furthermore, the organotin catalyst is one of stannous octoate, dibutyltin dilaurate, dibutyltin dioxalate, dibutyltin didodecylsulfide, or a mixture of several of them, preferably dibutyltin dilaurate.

[0059] The non-tin environmentally friendly catalyst is a mixture of one or more of triethylamine, triethylenediamine, dimethylcyclohexylamine, dimethylcyclohexylamine of tertiary amines, potassium isooctanoate, potassium oleate, bismuth isooctanoate and zinc isooctanoate of organic metals, preferably bismuth isooctanoate.

[0060] In a second aspect, the present invention also provides a method for preparing acrylonitrile-modified thermoplastic polyurethane, the specific steps of which are: blending three components a) acrylonitrile, b) polyol, and c) chain extender, adding solvent 2 to evenly mix the three components a) to c), then adding d) diisocyanate and stirring evenly, then adding e) catalyst and stirring evenly, reacting at 60 to 200° C., and removing the solvent to obtain acrylonitrile-modified thermoplastic polyurethane.

[0061] The solvent 2 is one or more of xylene, ethyl acetate, butyl acetate, dichloromethane, tetrahydrofuran, and toluene, preferably xylene, ethyl acetate, butyl acetate, and dichloromethane.

[0062] Or, a second method for preparing acrylpimarol-modified thermoplastic polyurethane, the specific steps are: a) acrylpimarol, b) polyol, c) chain extender, d) diisocyanate, e) catalyst, all components are blended, and extruded through an industrial twin-screw reaction to obtain acrylpimarol-modified thermoplastic polyurethane.

[0063] The present invention utilizes the reaction of the alcohol hydroxyl group of the diol compound with the isocyanate group of the diisocyanate to form an urethane chemical bond, and the polymerization reaction of the 2-2 system generates a long-chain linear polymer with thermoplastic properties, such as Figure 1 .

[0064] In the system of the present invention, propylene pinamarin reacts with diisocyanate to form a rigid urethane chain component;

[0065] Both polyols and chain extenders are long carbon chain diols, which also react with diisocyanates to form flexible chain components;

[0066] The product with better performance is obtained by the above-mentioned ratio of rigid chain to flexible chain. Finally, the polymerization reaction time is adjusted by adding a catalyst at room temperature.

[0067] The present invention is further explained below in conjunction with specific embodiments, but is not intended to limit the protection scope of the present invention.

[0068] The bio-based raw material information involved in the examples is as follows:

[0069] (1) Preparation of acrylpimaric acid: According to the literature (Wan Guoyun, Wang Zhenguo, Su Jianxiong. Preparation of acrylic rosin polyester fiberglass from rosin [J]. Plastic Industry, 1987, (01): 30-32+2), rosin and acrylic acid were added into a three-necked flask at a mass ratio of 4:25, and heated to 170°C for 2 h under nitrogen protection to isomerize the abietic acid in the rosin to generate L-pimaric acid. The temperature was then raised to 225°C for 2 h. Since the conjugated double bond of L-pimaric acid is S-cis, it has high reactivity, so it reacts with the dienophile acrylic acid to produce a light yellow transparent solid acrylpimaric acid by Diels-Alder reaction.

[0070] (2) Biobased acids: Biobased succinic acid, purchased from BioAmber; biobased sebacic acid, purchased from Hebei Kaide Biomaterials Co., Ltd.;

[0071] (3) Bio-based polyester polyol: Bio-based 1,3-propanediol, purchased from DuPont.

[0072] Preparation of bio-based poly(1,3-propylene succinate) diol: According to the literature (Liu Yiwu, Wang Qian, Tan Jinghua, et al. Synthesis and characterization of biodegradable poly(1,3-propylene succinate) diol / 1,3-propylene glycol ester [J]. Journal of Packaging, 2014, 6(01): 10-15), bio-based succinic acid and bio-based 1,3-propylene glycol were put into a three-necked flask equipped with a stirrer at a molar ratio of 1:1.2, and dibutyltin dilaurate was added at a mass fraction of 0.3% of the total amount of raw materials. The mixture was heated to 140°C under argon protection; after reacting for 1 hour, the mixture was switched to a reduced pressure reaction device and heated to 160°C; the vacuum degree of the flask was adjusted to -0.1 MPa and the reaction was carried out for 2 hours; the temperature was then raised to 190°C to continue the reaction; the reaction was stopped when the acid value was less than 1.5 mg KOH / g and the hydroxyl value reached a predetermined value. The hydroxyl value of 56 mg KOH / g corresponds to a number average molecular weight of 2000 g / mol, and the hydroxyl value of 112 KOH / g corresponds to a number average molecular weight of 1000 g / mol. The obtained product was purified and then dried under vacuum at 60° C. for 24 h.

[0073] Preparation of bio-based poly (1,3-propylene glycol sebacic acid) diol: According to the literature (Liu Quanyong, Tan Tianwei, Weng Jingyi, et al. Synthesis of poly (1,3-propylene glycol sebacic acid) ester under catalyst-free conditions and its molecular weight study [J]. Modern Chemical Industry, 2008, (S2): 169-173.), bio-based sebacic acid and bio-based 1,3-propylene glycol were mixed in a three-necked flask at a molar ratio of 1:1.1, and then heated and evacuated to melt them at 120°C and 2kPa. When the reaction monomers were completely melted, the magnetic stirrer was started to start the reaction; when the acid value was less than 1mg KOH / g and the hydroxyl value reached a predetermined value, the reaction was stopped. The hydroxyl value of 38mg KOH / g corresponds to a number average molecular weight of 3000g / mol, and the hydroxyl value of 112mg KOH / g corresponds to a number average molecular weight of 1000g / mol.

[0074] Preparation of bio-based poly 1,4-butylene sebacic acid diol was prepared according to the literature (Cai Guoxing, Wu Manjiang, Ai Li, Zhang Lijing. Study on the polymerization reaction of 1,4-butanediol and sebacic acid [J]. Chemistry and Bioengineering, 2008, (07): 17-19.)

[0075] Bio-based sebacic acid and petroleum-based 1,4-butanediol were added to a three-necked flask in a molar ratio of 1:1.2, and the temperature was raised to 140°C. After reacting for 1 hour, a solid-supported butyl titanate catalyst with a mass fraction of 1.2% of the total amount of raw materials was added, and then the temperature was raised to 160°C. When the acid value was less than 1 mg KOH / g and the hydroxyl value reached 28 mg KOH / g, the reaction was stopped, and the corresponding number average molecular weight was 4000 g / mol.

[0076] Preparation of bio-based poly 1,4-butylene succinate diol: According to the literature (Wu Jianning, Meng Guihua, Liu Zhiyong, et al. Synthesis and process research of poly butylene succinate diol [J]. Synthetic Materials Aging and Application, 2012, 41(02): 6-9+60.), bio-based succinic acid and petroleum-based 1,4-butanediol were added to a four-necked flask at a molar ratio of 1:1.3, and a stannous chloride catalyst with a mass fraction of 1.2% of the total amount of raw materials was added; a stirring device and a distillation device were installed; the oil bath temperature was controlled to 140°C, and the reaction was carried out under stirring for 1 hour. The reaction device was changed to a vacuum distillation device, stirred, and heated to 180°C at 10°C / 10min. The internal pressure was reduced to 1kPa and the reaction was carried out at a constant temperature; when the acid value was less than 1mg KOH / g and the hydroxyl value reached 56mg KOH / g, the reaction was stopped, and the corresponding number average molecular weight was 2000g / mol.

[0077] Preparation of bio-based poly(1,3-propylene glycol adipate) diol, according to the literature (Chen Si. Functionalization of carbon nanotubes and preparation and performance study of poly(1,3-propylene glycol adipate) diol-hydroxy carbon nanotube copolymer [J]. Materials Guide, 2012, 26 (S2): 64-68.)

[0078] Petroleum-based adipic acid and bio-based 1,3-propylene glycol are added to a three-necked flask in a molar ratio of 1:1.4, and stirred and heated in an oil bath at 200-300°C until almost no fraction is generated, and 0.3% of the mass of 1,3-propylene glycol is added as a butyl titanate catalyst; when the acid value is less than 1 mg KOH / g and the hydroxyl value reaches 56 mg KOH / g, the reaction is stopped, and the corresponding number average molecular weight is 2000 g / mol.

[0079] (4) Bio-based chain extender: Bio-based 1,3-propylene glycol, purchased from DuPont.

[0080] (5) Bio-based diisocyanates:

[0081] Bio-based 1,4-butanediisocyanate, according to the method reported in the literature (Zhang Yongzhen, Shi Sen, Li Yuan, et al. Preparation of biomass-based 1,4-butanediisocyanate and its application in medical polyurethane materials [J]. Polyurethane Industry, 2013, 28(6): 1-4), is prepared by hydrogenating bio-based succinic acid to synthesize bio-based 1,4-butanediamine, and then reacting it with phosgene to obtain bio-based 1,4-butanediisocyanate through a gas phase phosgene method.

[0082] Bio-based 1,5-pentane diisocyanate is prepared by thermally decomposing bio-based 1,5-pentanediamine through a phosgenation reaction according to the method disclosed in patent CN102782146.

[0083] Example 1

[0084] 9wt% of propylene pinol with a molecular weight of 346g / mol, 46wt% of PPSu (bio-based poly(1,3-propylene succinate diol) with a molecular weight of 2000g / mol), a total amount of diisocyanate of 32.5wt% (of which petroleum-based diisocyanate accounts for 70wt% and bio-based diisocyanate accounts for 30wt%), namely 22.75wt% MDI (4,4-diphenylmethane diisocyanate), 9.75wt% BDI (bio-based 1,4-butanediisocyanate), 12.4wt% PDO (bio-based 1,3-propylene glycol), and 0.01wt% bismuth isooctanoate are mixed evenly, and then subjected to twin-screw reaction extrusion (extruder temperature 160°C) to obtain a bio-based thermoplastic polyurethane elastomer.

[0085] Example 2

[0086] 9.2wt% of propylene rosin alcohol with a molecular weight of 346g / mol, 24.72wt% of PPSu (bio-based poly(1,3-propylene succinate diol) with a molecular weight of 1000g / mol), a total amount of diisocyanate of 43.5wt% (of which petroleum-based diisocyanate accounts for 60wt% and bio-based diisocyanate accounts for 40wt%), namely 26.1wt% MDI (4,4-diphenylmethane diisocyanate), 17.4wt% BDI (bio-based 1,4-butanediisocyanate), 22.47wt% PDO (bio-based 1,3-propylene glycol), and 0.01wt% bismuth isooctanoate are mixed evenly, and then subjected to twin-screw reaction extrusion (extruder temperature 180°C) to obtain a bio-based thermoplastic polyurethane elastomer.

[0087] Example 3

[0088] 9.4wt% of propylene rosin alcohol with a molecular weight of 346g / mol, 75.6wt% of PPSe (bio-based poly 1,3-propylene glycol sebacate) with a molecular weight of 3000g / mol, a total amount of diisocyanate of 12.15wt% (of which petroleum-based diisocyanate accounts for 50wt% and bio-based diisocyanate accounts for 50wt%), namely 6.08wt% HDI (hexamethylene diisocyanate), 6.07wt% PDI (bio-based 1,5-pentane diisocyanate), 2.84wt% PDO (bio-based 1,3-propylene glycol), and 0.01wt% bismuth isooctanoate are mixed evenly according to the formula ratio, and then subjected to twin-screw reaction extrusion (extruder temperature 160°C) to obtain a bio-based thermoplastic polyurethane elastomer.

[0089] Example 4

[0090] 6.8wt% of propylene rosin alcohol with a molecular weight of 346g / mol, 73.2wt% of PBSe (bio-based poly 1,4-butylene sebacate diol) with a molecular weight of 4000g / mol, a total amount of diisocyanate of 15.82wt% (of which petroleum-based diisocyanate accounts for 40wt% and bio-based diisocyanate accounts for 60wt%), namely 6.33wt% HMDI (4,4-dicyclohexylmethane diisocyanate), 9.49wt% PDI (bio-based 1,5-pentanediisocyanate), 4.17wt% PDO (bio-based 1,3-propylene glycol), and 0.01wt% bismuth isooctanoate are mixed evenly according to the formula ratio, and then subjected to twin-screw reaction extrusion (extruder temperature 170°C) to obtain a bio-based thermoplastic polyurethane elastomer.

[0091] Example 5

[0092] 47.01% propylene rosin alcohol with a molecular weight of 346g / mol and a total amount of diisocyanate of 52.97% (of which petroleum-based diisocyanate accounts for 64wt% and bio-based diisocyanate accounts for 36wt%), namely 33.97wt% MDI (4,4-diphenylmethane diisocyanate), 19wt% BDI (bio-based 1,4-butanediisocyanate), and 0.01wt% bismuth isooctanoate are mixed evenly, and then subjected to twin-screw reaction extrusion (extruder temperature 160°C) to obtain a bio-based thermoplastic polyurethane elastomer.

[0093] Comparative Example 1

[0094] 9.66wt% of propylene rosin alcohol with a molecular weight of 346g / mol, 51.95wt% of PBSu (bio-based polybutylene succinate diol) with a molecular weight of 2000g / mol, 28.36wt% of MDI (4,4-diphenylmethane diisocyanate), 10.02wt% of BDO (1,4-butanediol), and 0.01wt% of stannous octoate were mixed uniformly according to a formula ratio, and then subjected to twin-screw reactive extrusion (extruder temperature 180°C) to obtain a bio-based thermoplastic polyurethane elastomer.

[0095] Comparative Example 2

[0096] 8.22wt% of propylene rosin alcohol with a molecular weight of 346g / mol, 44.21wt% of PPA (bio-based poly(1,3-propylene adipate diol) with a molecular weight of 2000g / mol), 33.91wt% of HDI (4,4-hexamethylene diisocyanate), 13.65wt% of HDO (1,6-hexanediol), and 0.01wt% of dibutyltin dilaurate were mixed uniformly according to a formula ratio, and then subjected to twin-screw reactive extrusion (extruder temperature 180°C) to obtain a bio-based thermoplastic polyurethane elastomer.

[0097] Most of the raw materials used in Examples 1-4 are natural rosin derivatives and other bio-based materials, and organic bismuth is used instead of organic tin as a catalyst, which is green and environmentally friendly; the petroleum-based solvents or plasticizers and organic tin curing agents used in the comparative examples are even less environmentally friendly; the present invention reduces the impact of the volatilization of organic solvents on the environment, and at the same time reduces the reaction temperature, so that the possible energy consumption in actual production is reduced, the manufacturing cost in actual production is reduced, and the product is more competitive in the market.

[0098] The polyurethane synthesized by the present invention has a high solid content. By introducing a rigid rosin structure, the mechanical properties of the polyurethane are significantly increased compared with a comparative example, especially the hardness reaches 5H. Therefore, the polyurethane can be used as a rigid modified polyurethane material and mixed with other polyurethane materials for modification, thereby further expanding its application field. The modified thermoplastic polyurethane prepared by the present invention can be used as a reinforcing modified component and mixed with a polyurethane powder material to prepare a high-performance powder coating, thereby improving the adhesion, hardness, gloss, and comprehensive properties of the powder coating, such as hydrophobicity and corrosion resistance.

[0099]

[0100]

[0101]

[0102] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

[0103] It should be understood that the present invention is not limited to what has been described above and that various modifications and changes may be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A thermoplastic polyurethane modified with propylene pinamarin, characterized in that: Calculated by weight, the invention comprises: 5-50 wt% of propylene pinamacol, 0-75 wt% of polyol, 0-25 wt% of chain extender, 10-55 wt% of diisocyanate, and 0.001-0.1 wt% of catalyst, wherein the chain extender is not 0.

2. The propylene pinamarin modified thermoplastic polyurethane according to claim 1, characterized in that: Calculated by weight, the total content of bio-based components in acrylpimarol, polyol and chain extender is greater than or equal to 50wt%.

3. The acrylpimarol modified thermoplastic polyurethane according to claim 1, characterized in that: The polyol has a hydroxyl value ranging from 18 to 140 mg KOH / g; a moisture content less than or equal to 300 ppm; and an acid value less than or equal to 2 mg; In terms of mass percentage, the polyol comprises 50-100 wt % of bio-based polyester polyol and 0-50 wt % of petroleum-based polyol; The bio-based content of the bio-based polyester polyol is greater than or equal to 50 wt%.

4. The propylene pinamarin modified thermoplastic polyurethane according to claim 1, characterized in that: The catalyst comprises a non-tin environmentally friendly catalyst or a tin-containing catalyst; the catalyst content is less than or equal to 400 ppm; The organotin catalyst is one of stannous octoate, dibutyltin dilaurate, dibutyltin dioxalate, and dibutyltin didodecylsulfide; The non-tin environmentally friendly catalyst is one of triethylamine, triethylenediamine, dimethylcyclohexylamine, dimethylcyclohexylamine of tertiary amines, potassium isooctanoate, potassium oleate, bismuth isooctanoate and zinc isooctanoate of organic metals.

5. The method for preparing the propylene pinamarin modified thermoplastic polyurethane according to any one of claims 1 to 4, characterized in that: The steps include: Step 1: blending propylene pinamarin, polyol and chain extender, adding solvent thereto, and mixing evenly to obtain a mixed solution A; Step 2: adding diisocyanate and catalyst to the mixed solution A in sequence, stirring evenly and reacting at 60-200° C., and removing the solvent after the reaction to obtain propylene pinamarin modified thermoplastic polyurethane; The solvent is one or more of xylene, ethyl acetate, butyl acetate, dichloromethane, tetrahydrofuran, and toluene; Or, comprising the steps of: Propylene pimaric alcohol, polyol, chain extender, diisocyanate and catalyst are mixed and extruded through industrial twin-screw reaction to obtain thermoplastic polyurethane modified with propylene pimaric alcohol.

6. The method for preparing the propylene pinamarin modified thermoplastic polyurethane according to claim 5, characterized in that: The preparation method of propylene pimaric acid is as follows: dissolving propylene pimaric acid in a solvent, slowly adding a reducing agent under low temperature conditions and under the protection of an inert gas, reacting for 0.5 to 6 hours, and then heating to 40 to 80° C. to react for 6 to 24 hours; After the reaction is completed, the excess reducing agent is quenched with a quenching agent, deionized water is added and fully shaken, filtered, and vacuum filtered at 40-60°C until constant weight is reached; Add a non-water-soluble solvent to the constant-weight filtrate, shake it thoroughly, let it stand to separate the layers, remove the water layer, and perform high-vacuum rotary evaporation on the oil layer liquid to obtain a viscous liquid product having a diol structure - propylene pinamarin; The solvent is one or more mixed solvents selected from anhydrous tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, ethyl ether, ethyl butyl ether, dihexyl ether, dipentyl ether, and 3-methylfuran; The reducing agent is one or more mixtures of lithium aluminum hydride, sodium borohydride, potassium borohydride or dibutylaluminum hydride; The quenching agent is one or more of water, sodium hydroxide aqueous solution, sodium carbonate aqueous solution, sodium bicarbonate aqueous solution, hydrochloric acid solution or disulfuric acid solution; The non-aqueous solvent is a mixture of one or more of toluene, xylene, ethyl acetate, and butyl acetate; The low temperature condition is -10°C to 15°C, and the inert gas is preferably nitrogen or argon, or a mixture of the two.

7. The use of the propylene pinamarin modified thermoplastic polyurethane according to any one of claims 1 to 6, characterized in that: Used in the preparation of thermoplastic powder coatings.

Images