Propylene pinoresinol-modified thermoplastic polyurethane and method for preparing the same

Abstract

The application discloses a kind of propylene pimarol modified thermoplastic polyurethane and preparation method thereof, the application is according to weight fraction, including: propylene pimarol 5~50 parts, polyol 0~75 parts, chain extender 0~25 parts, diisocyanate 10~55 parts, catalyst 0.001~0.1 parts, wherein chain extender is not 0.The propylene pimarol modified thermoplastic polyurethane provided by the application introduces the trinuclear phenanthrene ring structure of rosin into the linear main chain structure of thermoplastic polyurethane by the reaction of dihydric alcohol of propylene pimarol and diisocyanate, which retains the rigid structure characteristics of rosin and the good flexibility of fatty six-membered ring non-planar structure compared to traditional carbon chain structure, so the coating prepared by it has better gloss, higher hardness, stronger adhesion, excellent comprehensive performance such as hydrophobicity, corrosion resistance and the like compared to traditional thermoplastic polyurethane material.

Description

Technical Field

[0001] This invention relates to the field of polyurethane materials technology, and in particular to a propylene-sinyl terpineol-modified thermoplastic polyurethane and its preparation method. Background Technology

[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 and aging resistance, as well as better biocompatibility and biological stability. At present, the medical device industry has a huge demand for medical-grade thermoplastic polyurethane elastomer, which is increasing year by year, and may gradually replace polyvinyl chloride as the main material for the production of medical catheters.

[0003] Currently, commercially available thermoplastic polyurethane elastomers mainly consist of three components: isocyanate, polyol, and chain extender, and the raw materials are all derived from fossil resources. However, with the continuous depletion of petroleum resources, finding new renewable raw materials has become imperative. Currently developed bio-based polyurethanes mainly include vegetable oil-based polyurethanes, polysaccharide-based polyurethanes, and rosin-based polyurethanes.

[0004] Patent CN109438653 discloses a method for preparing polyester polyols using bio-based acids such as succinic acid, sebacic acid, and polylactic acid, as well as bio-based alcohols and bio-based 1,3-propanediol, 1,2-propanediol, ethylene glycol, and 1,4-butanediol, thereby obtaining bio-based thermoplastic polyurethane elastomers. However, the resulting polyurethane requires excessively high reaction temperatures, which is detrimental to simplifying the production process and improving 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 biodegradation promoters, antioxidants, and plasticizers to obtain a high-bio-based composite material. This material exhibits good biodegradability, but its mechanical properties, especially hardness, are not excellent.

[0005] Therefore, it is of great significance to provide a low-cost method for preparing thermoplastic polyurethane. Summary of the Invention

[0006] In view of this, the present invention provides a propylene-pine alcohol modified thermoplastic polyurethane and its preparation method, so as to improve the mechanical properties of polyurethane while reducing production costs.

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

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

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

[0010] The polyols comprise, by weight percentage, 50-100 wt% bio-based polyester polyols and 0-50 wt% petroleum-based polyols;

[0011] The bio-based content in 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 dioxoate, and di(dodecyl sulfide)dibutyltin;

[0014] The non-tin environmentally friendly catalyst is one of the following: tertiary amines such as triethylamine, triethylenediamine, dimethylcyclohexylamine, and dimethylcyclohexylamine; and organometallic catalysts such as potassium isooctanoate, potassium oleate, bismuth isooctanoate, and zinc isooctanoate.

[0015] Secondly, the present invention also provides a method for preparing the above-mentioned propylene-piperyl alcohol modified thermoplastic polyurethane, comprising the following steps:

[0016] Step 1: Mix propylene pine alcohol, polyol, and chain extender together, then add solvent and mix thoroughly to obtain mixed solution A;

[0017] Step 2: Add diisocyanate and catalyst to mixed solution A in sequence, stir evenly, and react at 60-200℃. After the reaction, remove the solvent to obtain propylene-sinyl pineol modified thermoplastic polyurethane.

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

[0019] Alternatively, it may include the following steps:

[0020] Acrylic pine alcohol, polyol, chain extender, diisocyanate and catalyst are blended and then subjected to industrial twin-screw reactive extrusion to obtain propylene pine alcohol modified thermoplastic polyurethane.

[0021] Preferably, the preparation method of the propylene pinolate is as follows: dissolve propylene pinolate in a solvent, and under low temperature conditions and inert gas protection, slowly add a reducing agent and react for 0.5 to 6 hours, and then raise the temperature to 40 to 80°C and react for 6 to 24 hours;

[0022] After the reaction is complete, excess reducing agent is quenched with a quenching agent, deionized water is added and shaken thoroughly, filtered, and then vacuum filtered at 40-60℃ until constant weight is achieved.

[0023] Add a non-aqueous solvent to the constant-weight filtrate, shake thoroughly, allow to stand and separate into layers, remove the water layer, and perform high-vacuum rotary evaporation on the oil layer to obtain a viscous liquid product with a diol structure - propylene pineol.

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

[0025] The reducing agent is one or more 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 alkyl sulfuric acid solution;

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

[0028] The low-temperature conditions are -10℃ to 15℃, and the inert gas is preferably one or a mixture of two of nitrogen or argon.

[0029] This invention provides a propylene-piperidine modified thermoplastic polyurethane and its preparation method. Compared with existing thermoplastic polyurethanes, this invention uses rosin, a bio-based material, as a raw material to replace traditional petroleum-based raw materials, thus exhibiting green and environmentally friendly characteristics. Furthermore, the propylene-piperidine modified thermoplastic polyurethane provided by this 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-piperidine with diisocyanate. Compared with the traditional carbon chain structure, this retains both the rigid structural characteristics of rosin and the good flexibility of the non-planar structure of the aliphatic six-membered ring. Therefore, the coating film prepared by this invention has better gloss, higher hardness, stronger adhesion, and superior comprehensive properties such as hydrophobicity and corrosion resistance compared to traditional thermoplastic polyurethane materials.

[0030] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit the disclosure of the present invention. Attached Figure Description

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

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the preparation reaction process of a propylene-sinyl pine alcohol modified thermoplastic polyurethane provided in Embodiment 1 of the present invention. Detailed Implementation

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

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

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

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

[0038] a: The preparation method of the propylene pinocyanol is as follows: propylene pinocyanic acid is dissolved in solvent 1. Under low temperature conditions and inert gas protection, a reducing agent is slowly added. After the reducing agent is added, the reaction proceeds for 0.5–6 hours, and then the temperature is raised to 40–80°C for 6–24 hours. After the reaction is complete, excess reducing agent is quenched with a quenching agent. Then, deionized water is added, and the mixture is thoroughly shaken. After filtration, the mixture is vacuum filtered at 40–60°C until constant weight is achieved. A non-aqueous solvent is added to the constant-weight filtrate, and after thorough shaking, the mixture is allowed to stand and separate into layers. The aqueous layer is removed, and the oil layer is subjected to high-vacuum rotary evaporation to obtain a viscous liquid product with a diol structure—propylene pinocyanol.

[0039] Solvent 1 is preferably one or a mixture 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 conditions can be achieved by liquid nitrogen freezing or by maintaining a temperature of -10℃ to 15℃ using temperature control equipment.

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

[0042] The reducing agent is preferably one or a mixture 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 alkyl sulfuric acid solution.

[0044] The non-aqueous solvent is preferably one or a mixture 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 components, the polyol comprises 50-100 wt% bio-based polyester polyol and 0-50 wt% petroleum-based polyol, preferably 70-100 wt% bio-based polyester polyol and 0-30 wt% petroleum-based polyol.

[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 polyols include one or more of petroleum-based 1,3-propanediol, ethylene glycol, 1,2-propanediol, 1,4-butanediol, dipropylene glycol, hexanediol, diethylene glycol, methylpropanediol, neopentyl glycol, and petroleum-based polyester polyols. Preferably, petroleum-based polyester polyols are 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. The small molecule alcohols can be bio-based, petroleum-based, or both. The bio-based acid is primarily one or more of bio-based succinic acid, sebacic acid, and polylactic acid. The bio-based small molecule alcohol is primarily one or more of bio-based 1,3-propanediol, bio-based 1,2-propanediol, 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-propanediol, ethylene glycol, 1,2-propanediol, 1,4-butanediol, dipropylene glycol, hexanediol, diethylene glycol, methylpropanediol, and neopentyl glycol.

[0049] The bio-based polyester polyol has a hydroxyl value ranging from 18 to 140 mg KOH / g, preferably from 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 bio-based 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 components.

[0050] The bio-based polyester polyol is preferably one or more of poly(1,3-propanediol succinate) diol (PPSu), poly(butylene succinate) diol (PBSu), poly(1,3-propanediol sebacate) diol (PPSe), and poly(butylene sebacate) diol (PBSe).

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

[0052] The petroleum-based chain extender is one or a mixture of several of the following: petroleum-based ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,4-butanediol, dipropylene glycol, hexanediol, diethylene glycol, methylpropanediol, and neopentyl glycol. Petroleum-based 1,4-butanediol is preferred.

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

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

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

[0056] Further, the petroleum-based diisocyanate is one or a mixture of hexamethylene diisocyanate, 4,4-diphenylmethane diisocyanate, 4,4-dicyclohexylmethane diisocyanate, toluene diisocyanate, isophorone diisocyanate, isophthalic diisocyanate, and 1,5-naphthalene diisocyanate. Preferably, 4,4-diphenylmethane diisocyanate or hexamethylene diisocyanate is preferred.

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

[0058] Furthermore, the organotin catalyst is one or a mixture of several of the following: stannous octoate, dibutyltin dilaurate, dibutyltin dioxane, and di(dodecyl sulfide)dibutyltin. Dibutyltin dilaurate is preferred.

[0059] The non-tin environmentally friendly catalyst is one or a mixture of tertiary amines such as triethylamine, triethylenediamine, dimethylcyclohexylamine, and dimethylcyclohexylamine; and organometallic catalysts such as potassium isooctanoate, potassium oleate, bismuth isooctanoate, and zinc isooctanoate. Bismuth isooctanoate is preferred.

[0060] Secondly, the present invention also provides a method for preparing propylene-sinyl pineol modified thermoplastic polyurethane, the specific steps of which are as follows: mixing three components a) propylene-sinyl pineol, b) polyol and c) chain extender, adding solvent 2 to mix the three components a) to c) uniformly, 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 propylene-sinyl pineol 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] Alternatively, a second method for preparing propylene-sinyl pineol-modified thermoplastic polyurethane includes the following steps: blending a) propylene-sinyl pineol, b) polyol, c) chain extender, d) diisocyanate, and e) catalyst, and extruding the mixture using an industrial twin-screw extruder to obtain propylene-sinyl pineol-modified thermoplastic polyurethane.

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

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

[0065] Both the polyol and the chain extender are long-chain diols, which also react with diisocyanates to form flexible chain components.

[0066] A product with superior performance was obtained by adjusting the ratio of rigid to flexible chains as described above. Finally, the polymerization reaction time was adjusted by adding a catalyst at room temperature.

[0067] The present invention will be further explained and described below with reference to specific embodiments, but this is not intended to limit the scope of protection of the present invention.

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

[0069] (1) Preparation of propylene-piperidine: According to the literature (Wan Guoyun, Wang Zhenguo, Su Jianxiong. Preparation of rosin-acrylic acid-rosin-polyester fiberglass [J]. Plastics Industry, 1987, (01): 30-32+2.), rosin and acrylic acid were added to a three-necked flask at a mass ratio of 4:25. The mixture was heated to 170℃ for 2 hours under nitrogen protection to induce isomerization of the abietic resin acid in the rosin, generating L-piperidine. Then, the temperature was increased to 225℃ for 2 hours. Due to the high reactivity of the conjugated double bond of L-piperidine, it underwent a Diels-Alder reaction with the dienophile acrylic acid to obtain a pale yellow transparent solid of propylene-piperidine.

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

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

[0072] The preparation of bio-based poly(1,3-propanediol) succinate was carried out according to the literature (Liu Yiwu, Wang Qian, Tan Jinghua, et al. Synthesis and characterization of biodegradable poly(butylene succinate / 1,3-propanediol) ester [J]. Journal of Packaging, 2014, 6(01): 10-15.). Bio-based succinate and bio-based 1,3-propanediol were added to a three-necked flask equipped with a stirrer at a molar ratio of 1:1.2, and 0.3% (by mass) of dibutyltin dilaurate was added. The mixture was heated to 140°C under argon protection; after reacting for 1 hour, the reaction was switched to a reduced-pressure reaction apparatus and heated to 160°C; the vacuum degree of the flask was adjusted to -0.1 MPa, and the reaction was continued 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 the 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] The preparation of bio-based poly(1,3-propanediol sebacate) was carried out according to the literature (Liu Quanyong, Tan Tianwei, Weng Jingyi, et al. Synthesis and molecular weight study of poly(1,3-propanediol sebacate) ester under catalyst-free conditions [J]. Modern Chemical Industry, 2008, (S2): 169-173.). Bio-based sebacate and bio-based 1,3-propanediol were pre-mixed in a three-necked flask at a molar ratio of 1:1.1, and then heated and evacuated to melt them at 120℃ and 2kPa. After the reactants were completely melted, a magnetic stirrer was started to begin the reaction; the reaction was stopped when the acid value was less than 1 mg KOH / g and the hydroxyl value reached the predetermined value. A hydroxyl value of 38 mg KOH / g corresponds to a number-average molecular weight of 3000 g / mol, and a hydroxyl value of 112 mg KOH / g corresponds to a number-average molecular weight of 1000 g / mol.

[0074] The preparation of bio-based poly(1,4-butanediol) sebacic acid was carried out according to the literature (Cai Guoxing, Wu Manjiang, Ai Li, Zhang Lijing. Study on polymerization reaction of 1,4-butanediol and sebacic acid [J]. Chemical and Biological Engineering, 2008, (07): 17-19.).

[0075] Bio-based sebacic acid and petroleum-based 1,4-butanediol were added to a three-necked flask at a molar ratio of 1:1.2. The mixture was heated to 140°C and reacted for 1 hour. Then, 1.2% by mass of a supported tetrabutyl titanate catalyst (based on the total amount of raw materials) was added, and the mixture was heated to 160°C. The reaction was stopped when the acid value was less than 1 mg KOH / g and the hydroxyl value reached 28 mg KOH / g. At this point, the corresponding number-average molecular weight was 4000 g / mol.

[0076] The preparation of bio-based polybutylene succinate diol was carried out according to the literature (Wu Jianning, Meng Guihua, Liu Zhiyong, et al. Synthesis and process study of polybutylene succinate [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 1.2% stannous chloride catalyst (mass fraction of the total raw materials) was added. A stirring device and a distillation device were installed. The oil bath temperature was controlled at 140℃, and the reaction was carried out for 1 hour under stirring. The reaction device was then changed to a vacuum distillation device, stirred, and heated to 180℃ at 10℃ / 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. At this time, the corresponding number-average molecular weight was 2000g / mol.

[0077] The preparation of bio-based poly(1,3-propanediol adipate) was based on the literature (Chen Si. Functionalization treatment of carbon nanotubes and preparation and performance study of poly(1,3-propanediol adipate)-hydroxy carbon nanotube copolymer [J]. Materials Reports, 2012, 26(S2): 64-68.).

[0078] Petroleum-based adipic acid and bio-based 1,3-propanediol were added to a three-necked flask at a molar ratio of 1:1.4. The mixture was stirred and heated in an oil bath at 200–300 °C until almost no distillate was formed. Then, 0.3% by mass of butyl titanate catalyst (based on the mass of 1,3-propanediol) was added. The reaction was stopped when the acid value was less than 1 mg KOH / g and the hydroxyl value reached 56 mg KOH / g. At this point, the corresponding number-average molecular weight was 2000 g / mol.

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

[0080] (5) Bio-based diisocyanates:

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

[0082] Bio-based 1,5-pentanediisocyanate is prepared by thermal decomposition of bio-based 1,5-pentanediamine via phosgenation reaction according to the method disclosed in patent CN102782146.

[0083] Example 1

[0084] A bio-based thermoplastic polyurethane elastomer was prepared by uniformly mixing 9 wt% of propylene pineol with a molecular weight of 346 g / mol, 46 wt% of PPSu (bio-based poly(1,3-propanediol) succinate) with a molecular weight of 2000 g / mol, a total diisocyanate content of 32.5 wt% (of which petroleum-based diisocyanate accounted for 70 wt% and bio-based diisocyanate accounted for 30 wt%), namely 22.75 wt% MDI (4,4-diphenylmethane diisocyanate), 9.75 wt% BDI (bio-based 1,4-butanediisocyanate), 12.4 wt% PDO (bio-based 1,3-propanediol), and 0.01 wt% bismuth isooctanoate, and then by twin-screw reactive extrusion (extruder temperature 160℃).

[0085] Example 2

[0086] A bio-based thermoplastic polyurethane elastomer was prepared by uniformly mixing 9.2 wt% of propylene rosin alcohol with a molecular weight of 346 g / mol, 24.72 wt% of PPSu (bio-based poly(1,3-propanediol) succinate) with a molecular weight of 1000 g / mol, a total diisocyanate content of 43.5 wt% (of which petroleum-based diisocyanate accounted for 60 wt% and bio-based diisocyanate accounted for 40 wt%), namely 26.1 wt% MDI (4,4-diphenylmethane diisocyanate), 17.4 wt% BDI (bio-based 1,4-butanediisocyanate), 22.47 wt% PDO (bio-based 1,3-propanediol), and 0.01 wt% bismuth isooctanoate, and then subjected to twin-screw reactive extrusion (extruder temperature 180℃).

[0087] Example 3

[0088] A bio-based thermoplastic polyurethane elastomer was prepared by uniformly mixing 9.4 wt% of propylene rosin alcohol with a molecular weight of 346 g / mol, 75.6 wt% of PPSe (bio-based poly(1,3-propanediol sebacate) with a molecular weight of 3000 g / mol), a total diisocyanate content of 12.15 wt% (of which petroleum-based diisocyanate accounted for 50 wt% and bio-based diisocyanate accounted for 50 wt%), namely 6.08 wt% HDI (hexamethylene diisocyanate), 6.07 wt% PDI (bio-based 1,5-pentanediisocyanate), 2.84 wt% PDO (bio-based 1,3-propanediol), and 0.01 wt% bismuth isooctanoate according to the formulation ratio, and then by twin-screw reactive extrusion (extruder temperature 160℃).

[0089] Example 4

[0090] A bio-based thermoplastic polyurethane elastomer was prepared by uniformly mixing 6.8 wt% of propylene rosin alcohol with a molecular weight of 346 g / mol, 73.2 wt% of PBSe (bio-based poly(1,4-butanediol sebacate) with a molecular weight of 4000 g / mol), a total diisocyanate content of 15.82 wt% (of which petroleum-based diisocyanate accounted for 40 wt% and bio-based diisocyanate accounted for 60 wt%), namely 6.33 wt% HMDI (4,4-dicyclohexylmethane diisocyanate), 9.49 wt% PDI (bio-based 1,5-pentanediisocyanate), 4.17 wt% PDO (bio-based 1,3-propanediol), and 0.01 wt% bismuth isooctanoate according to the formulation ratio, and then extruding the mixture through a twin-screw reactive extruder (extruder temperature 170℃).

[0091] Example 5

[0092] A bio-based thermoplastic polyurethane elastomer was prepared by uniformly mixing 47.01% propylene rosin alcohol with a molecular weight of 346 g / mol, 52.97% total diisocyanate (of which petroleum-based diisocyanate accounted for 64 wt% and bio-based diisocyanate accounted for 36 wt%), namely 33.97 wt% MDI (4,4-diphenylmethane diisocyanate), 19 wt% BDI (bio-based 1,4-butanediisocyanate), and 0.01 wt% bismuth isooctanoate, and then by twin-screw reactive extrusion (extruder temperature 160℃).

[0093] Comparative Example 1

[0094] A bio-based thermoplastic polyurethane elastomer was prepared by uniformly mixing 9.66 wt% of propylene rosin alcohol with a molecular weight of 346 g / mol, 51.95 wt% of PBSu (bio-based polybutylene succinate diol) with a molecular weight of 2000 g / mol, 28.36 wt% of MDI (4,4-diphenylmethane diisocyanate), 10.02 wt% of BDO (1,4-butanediol), and 0.01 wt% of stannous octoate according to the formulation ratio, and then extruding the mixture by twin-screw reactive extrusion (extruder temperature 180℃).

[0095] Comparative Example 2

[0096] A bio-based thermoplastic polyurethane elastomer was prepared by uniformly mixing 8.22 wt% of propylene rosin alcohol with a molecular weight of 346 g / mol, 44.21 wt% of PPA (bio-based poly(1,3-propanediol adipate) with a molecular weight of 2000 g / mol), 33.91 wt% of HDI (4,4-hexamethylene diisocyanate), 13.65 wt% of HDO (1,6-hexanediol), and 0.01 wt% of dibutyltin dilaurate according to the formulation ratio, and then extruding the mixture through a twin-screw reactive extruder (extruder temperature 180℃).

[0097] The raw materials used in Examples 1-4 are mostly 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 less environmentally friendly. This invention reduces the impact of organic solvent volatilization on the environment, and at the same time lowers the reaction temperature, which reduces the energy consumption that may be needed in actual production, reduces the manufacturing cost in actual production, and makes the products more competitive in the market.

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

[0099]

[0100]

[0101]

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

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

Claims

1. A propylene-piperyl alcohol-modified thermoplastic polyurethane, characterized in that, The composition, by weight parts, includes: 5-50 wt% propylene pine alcohol, 0-75 wt% polyol, 0-25 wt% chain extender, 10-55 wt% diisocyanate, and 0.001-0.1 wt% catalyst, wherein the chain extender is not 0 wt%.

2. The propylene-sinyl terpineol-modified thermoplastic polyurethane according to claim 1, characterized in that, The total content of bio-based components in propylene pine alcohol, polyol, and chain extender is greater than or equal to 50 wt% by mass percentage.

3. The propylene-sinyl terpineol-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 of less than or equal to 300 ppm; and an acid value of less than or equal to 2 mg KOH / g. By mass percentage, the polyol comprises 50-100 wt% bio-based polyester polyol and 0-50 wt% petroleum-based polyol. The bio-based content in the bio-based polyester polyol is greater than or equal to 50 wt%.

4. The propylene-piperyl alcohol-modified thermoplastic polyurethane according to claim 1, characterized in that, The catalyst includes one of the following: a non-tin environmentally friendly catalyst or a tin-containing catalyst; the catalyst content is less than or equal to 400 ppm; the tin-containing catalyst is one of the following: stannous octoate, dibutyltin dilaurate, dibutyltin dioxane, and di(dodecyl sulfide)dibutyltin; the non-tin environmentally friendly catalyst is one of the following: tertiary amines such as triethylamine, triethylenediamine, and dimethylcyclohexylamine; organometallic catalysts such as potassium isooctanoate, potassium oleate, bismuth isooctanoate, and zinc isooctanoate.

5. The method for preparing the propylene-sinyl terpineol-modified thermoplastic polyurethane according to any one of claims 1-4, characterized in that, The process includes the following steps: Step 1: Blend propylene pineol, polyol, and chain extender, then add solvent and mix thoroughly to obtain mixed solution A; Step 2: Add diisocyanate and catalyst sequentially to mixed solution A, stir thoroughly, and react at 60~200℃. After the reaction, remove the solvent to obtain propylene pineol-modified thermoplastic polyurethane; wherein the solvent is one or more of xylene, ethyl acetate, butyl acetate, dichloromethane, tetrahydrofuran, and toluene; or, the process includes the following steps: Blend propylene pineol, polyol, chain extender, diisocyanate, and catalyst, and extrude via an industrial twin-screw extruder to obtain propylene pineol-modified thermoplastic polyurethane.

6. The preparation method of propylene-piperyl alcohol modified thermoplastic polyurethane according to claim 5, characterized in that, The preparation method of the propylene pineol is as follows: propylene pine acid is dissolved in a solvent, and a reducing agent is slowly added under low temperature and inert gas protection, followed by a reaction for 0.5-6 hours. Then, the temperature is raised to 40-80℃ and the reaction is continued for 6-24 hours. After the reaction, excess reducing agent is quenched with a quenching agent, deionized water is added, and the mixture is shaken thoroughly. After filtration, the mixture is vacuum filtered at 40-60℃ until constant weight is achieved. A non-aqueous solvent is added to the constant-weight filtrate, and after thorough shaking, the mixture is allowed to stand and separate into layers. The water layer is removed, and the oil layer is subjected to high-vacuum rotary evaporation to obtain a viscous liquid product with a diol structure—propylene pineol. The solvent is one or more mixed solvents selected from anhydrous tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethyl ether, ethyl butyl ether, dihexyl ether, dipentyl ether, and 3-methylfuran. The reducing agent is one or more 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 alkylsulfuric acid solution; the non-aqueous solvent is one or more of toluene, xylene, ethyl acetate, or butyl acetate; the low temperature condition is -10℃ to 15℃, and the inert gas is one or a mixture of two of nitrogen or argon.

7. The application of the propylene-sinyl terpineol modified thermoplastic polyurethane prepared by the preparation method of any one of claims 1-4 or any one of claims 5-6, characterized in that, It is used in the preparation of thermoplastic powder coatings.

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