Polyester resin and preparation method therefor, polyester pressure-sensitive adhesive and pressure-sensitive adhesive product

Abstract

A polyester resin, a preparation method therefor, and a polyester pressure-sensitive adhesive using the polyester resin. The polyester resin comprises a copolymer of a carboxyl-terminated polyester, an amorphous carbon dioxide-based polyester diol, and a modified diol, wherein the ratio by weight in parts of the carboxyl-terminated polyester to the amorphous carbon dioxide-based polyester diol to the modified diol is (10-30):(50-99):(2-30). The preparation method for the polyester resin comprises: putting raw materials into a reaction kettle, raising the temperature to 100-180℃, then adding a catalyst in an amount of 1‰ to 2% of the total mass of the raw materials, performing vacuum polycondensation and cooling to obtain the polyester resin.

Description

Polyester resin, preparation method thereof, polyester pressure-sensitive adhesive and pressure-sensitive adhesive product

[0001] The present disclosure claims priority to the Chinese patent application No. 202410739799X, filed on June 7, 2024, and entitled "Polyester resin, preparation method thereof, polyester pressure-sensitive adhesive and pressure-sensitive adhesive product", the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application belongs to the technical field of pressure-sensitive adhesive, in particular, the present application relates to polyester resin, preparation method thereof, polyester pressure-sensitive adhesive and pressure-sensitive adhesive product. BACKGROUND

[0003] Pressure-sensitive adhesive is a viscoelastic body with both viscous and elastic properties. It can be used to bond any smooth surfaces immediately under pressure. At the same time, if the bonded surface is damaged, the adhesive will not contaminate the surface. In recent years, with the increasing demand for packaging, office supplies and various labels, the demand for pressure-sensitive adhesive is also increasing.

[0004] The components of commonly used pressure-sensitive adhesive include three main components: base resin, tackifying resin and plasticizer. The base resin is used to improve the cohesion of the pressure-sensitive adhesive, and the tackifying resin provides the initial adhesion performance. However, the addition of tackifying resin in the traditional pressure-sensitive adhesive formula makes the base resin have pressure-sensitive properties, but significantly weakens the cohesion performance of the base resin, resulting in a decrease in the overall peel strength and tack of the pressure-sensitive adhesive tape. Because the conventional base resin does not contain long-chain branched structures, the base resin and the tackifying resin often belong to different types of resin, and the compatibility of the base resin and the tackifying resin is poor, which significantly affects the tack of the pressure-sensitive adhesive.

[0005] US20170283666A1 discloses a pressure-sensitive adhesive composition comprising a block copolymer, the block copolymer comprising a first block having a glass transition temperature of 50℃ or higher, and a second block having a glass transition temperature of -10℃ or lower. The first block can be (meth)acrylic alkyl ester, and the second block can be alkyl acrylate of 1 to 4 carbon atoms. However, this pressure-sensitive adhesive composition has the defects of poor tack and low peel strength.

[0006] Chinese patent application CN117447954A discloses a degradable hot melt pressure sensitive adhesive, which comprises the following components in parts by mass: 65-85 parts of degradable plastic, 5-25 parts of degradable tackifying resin, 1-9 parts of degradable plasticizer, 0-10 parts of filler, and 1 part of antioxidant, wherein the degradable plastic is one or more of polybutylene succinate, polylactic acid, polyglycolic acid, polybutylene terephthalate-adipate, and polypropylene carbonate, and the degradable tackifying resin is one or more of rosin, hydrogenated rosin, disulfide rosin, esterified rosin, carbon five petroleum resin, carbon nine petroleum resin, and terpene resin. However, the adhesion and tack of the pressure sensitive adhesive are not good.

[0007] Chinese patent application CN105802145A discloses a biodegradable thermoplastic elastomer, which is composed of the following components: 20-120 parts of biodegradable resin, 10-120 parts of filler, 0.2-5 parts of coupling agent, 0.03-5 parts of crosslinking agent, 0.1-10 parts of co-crosslinking agent, 0.2-10 parts of slip agent, 5-100 parts of plasticizer, and 0.1-40 parts of compatibilizer. The biodegradable resin is one or more of polybutylene succinate, polybutylene succinate-adipate, polybutylene adipate-terephthalate, polylactic acid, polypropylene carbonate, polycaprolactone, polyhydroxyalkanoate, and polyvinyl alcohol. The adhesion and tack of the elastomer cannot meet the requirements of pressure sensitive adhesive.

[0008] Chinese patent application CN117384577A discloses a degradable pressure sensitive adhesive material based on carbon dioxide, which is prepared by adding diacetyl-L-tartaric anhydride in the polymerization reaction of carbon dioxide and epoxide through a ternary polymerization reaction. However, when it is used as a pressure sensitive adhesive resin to prepare a pressure sensitive adhesive, the compatibility with tackifying resin is poor, the degree of phase separation is obvious, and the adhesion and tack of the pressure sensitive adhesive cannot meet the requirements.

[0009] Therefore, the base resin in the prior art cannot provide the required peel strength and adhesion. SUMMARY

[0010] Therefore, the base resin in the prior art cannot provide the required peel strength and adhesion.

[0011] In a first aspect, the present application relates to a polyester type resin, which is a copolymer of carboxyl-terminated polyester, non-crystalline carbon dioxide-based polyester diol, and modified diol, and the mass ratio of the carboxyl-terminated polyester, the non-crystalline carbon dioxide-based polyester diol, and the modified diol is (10-30):(50-99):(2-30), and the structure of the modified diol is shown in Formula 1, Formula 2, or Formula 3,

[0012] Formula 1,

[0013] Formula 2,

[0014] Formula 3

[0015] wherein:

[0016] R1 is C1-12 alkyl;

[0017] R2 is C1-12 alkyl;

[0018] R3 is C1-12 alkyl;

[0019] R4 is H or C1-12 alkyl;

[0020] R5 is C1-12 alkyl.

[0021] In a second aspect, the present application relates to a preparation method of the polyester resin, comprising the following steps:

[0022] The carboxyl-terminated polyester, the non-crystalline carbon dioxide-based polyester diol and the modified diol are put into a reaction kettle according to the mass fraction of (10-30):(50-99):(2-30), and after being heated to 100-180℃, 1‰-2% of the total mass of the carboxyl-terminated polyester, the non-crystalline carbon dioxide-based polyester diol and the modified diol is added as a catalyst, vacuum polycondensation is carried out, and cooling is performed to obtain the polyester resin.

[0023] In a third aspect, the present application further relates to a polyester pressure-sensitive adhesive, comprising the following components calculated by mass fraction: 50-99 parts of the polyester resin, and 0.1-10 parts of an additive.

[0024] In a fourth aspect, the present application further relates to a pressure-sensitive adhesive product, comprising a substrate and a pressure-sensitive adhesive layer attached to the substrate, wherein the pressure-sensitive adhesive layer comprises the polyester pressure-sensitive adhesive.

[0025] Therefore, the polyester resin has excellent performance, and the polyester pressure-sensitive adhesive prepared by the polyester resin has more excellent peel strength and bonding performance than the existing pressure-sensitive adhesive. BRIEF DESCRIPTION OF DRAWINGS

[0026] FIG. 1 is an infrared spectrum of the modified diol 1. DETAILED DESCRIPTION

[0027] The details of one or more embodiments of the application are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the application will be apparent from the description, drawings, and claims.

[0028] Regarding the first aspect of the present application, the polyester resin comprises a modified diol of formula 1, formula 2 or formula 3, which has a side chain, and the side chain contains an ester group, the modified diol and a non-crystalline carbon dioxide-based polyester diol, a carboxyl-terminated polyester are reacted in a certain proportion, and the polyester resin prepared contains a carboxyl-terminated polyester segment, a non-crystalline carbon dioxide-based polyester segment and a side chain segment. The carboxyl-terminated polyester segment is a hard segment, which can be used to ensure the cohesive strength of the polyester resin. The non-crystalline carbon dioxide-based polyester segment is a soft segment, which can ensure the elasticity of the polyester resin. The modified diol segment contains a side chain, which is introduced into the polyester resin, so that the branching degree of the polyester resin is increased, the glass transition temperature is reduced, and the overall molecular chain activity of the resin is enhanced. The ester group contained in the side chain can provide a large number of hydrogen bonds, which is easy to form hydrogen bond adhesion with the bonding base material, and the initial adhesion is good.

[0029] In one embodiment, R1 can be a C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12 alkyl group, and R1 is preferably a C1-4 alkyl group.

[0030] In one embodiment, R2 can be a C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12 alkyl group, and R2 is preferably a C1-4 alkyl group.

[0031] In one embodiment, R3 can be a C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12 alkyl group, and R3 is preferably a C1-4 alkyl group.

[0032] In one embodiment, R4 can be H, or a C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12 alkyl group, and R4 is preferably a C1-4 alkyl group.

[0033] In one embodiment, R5 can be a C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12 alkyl group, and R5 is preferably a C1-4 alkyl group.

[0034] For the polyester resin described in the present application, a certain amount of modified diol needs to be added to ensure that the polyester resin has the required degree of branching and hydrogen bonding, thereby having good initial adhesion and sustained adhesion performance, and thus the required mass fraction is 3 or more. If too much modified diol is added, the required ratio of hard segment and soft segment will decrease, affecting the performance of the polyester resin. Therefore, the mass fraction of the modified diol should be 30 or less. In one embodiment, the mass fraction of the modified diol is preferably 4 to 25, more preferably 5 to 20, and still more preferably 7, 9, 11, 13, 15, 17, or 19.

[0035] In one embodiment, the number average molecular weight of the carboxyl-terminated polyester can be 1,000 to 3,000. Since the molecular weight of each segment affects the performance of the polyester resin, for the carboxyl-terminated polyester, the higher the molecular weight, the stronger the crystallinity, and the stronger the ability to act as a physical crosslinking point. In order to achieve better performance, the number average molecular weight of the carboxyl-terminated polyester can be 1,000 or more, but too high a molecular weight results in stronger crystallinity, which makes the degree of microphase separation of the polyester pressure-sensitive adhesive larger, thereby causing the performance of the polyester pressure-sensitive adhesive to decrease. The number average molecular weight of the carboxyl-terminated polyester can be 3,000 or less, and specifically, the number average molecular weight of the carboxyl-terminated polyester can be 1,200, 1,400, 1,600, 1,800, 2,000, 2,200, 2,400, 2,600, 2,800, or 2,900.

[0036] In one embodiment, the mass fraction of the carboxyl-terminated polyester is 10 to 30. Since the carboxyl-terminated polyester contains carboxyl groups, it can act as a physical crosslinking point to form a polyester resin with a carbon dioxide-based polyester diol, thereby increasing the cohesive strength of the overall resin and enabling it to be applied in the field of pressure-sensitive adhesives to meet the adhesion performance of pressure-sensitive adhesives. The mass fraction of the carboxyl-terminated polyester can be 10 parts or more. As the content increases, the cohesive performance of the polyester resin increases, but too high a content of the carboxyl-terminated polyester increases the degree of phase separation, thereby decreasing the performance of the elastomer and causing the performance of the subsequent pressure-sensitive adhesive to decrease. In addition, too high a content of the carboxyl-terminated polyester increases the degree of physical entanglement of the elastomer, thereby decreasing the degradation rate of the elastomer. Therefore, the mass fraction of the carboxyl-terminated polyester is controlled to be 30 parts or less. Specifically, the mass fraction of the carboxyl-terminated polyester can be 12, 14, 16, 18, 20, 22, 24, 26, or 28.

[0037] In one embodiment, the carboxyl-terminated polyester is polymerized from a C3-7 diacid and a C3-7 diol.

[0038] In one embodiment, the carboxyl-terminated polyester is preferably polybutylene succinate (PBS). PBS is a new type of biodegradable polymer material, and its degradation mechanism is: first through the hydrolysis of C-O bond, and then further degradation under the action of enzymes. PBS is a crystalline material, which can be used as a physical crosslinking point to form a copolyester elastomer with polycarbonate, thereby improving the cohesive strength of the overall resin, so that it can be applied in the field of pressure-sensitive adhesive, and meet the higher bonding requirements of pressure-sensitive adhesive, and the raw material of PBS is derived from biomass, which is the second type of carbon source, and has good degradation performance.

[0039] In one embodiment, the carboxyl-terminated polybutylene succinate has a hydroxyl value of 37.4-112 mgKOH / g and a molecular weight of 1,000-3,000.

[0040] In one embodiment, the number average molecular weight of the non-crystalline carbon dioxide-based polyester diol is 2,000-4,000. If the molecular weight of the non-crystalline carbon dioxide-based polyester diol segment is too small, the segment is too short, and the elasticity of the polyester resin will be reduced, so the number average molecular weight is preferably greater than 2,000. If the molecular weight is too large, the content of the carboxyl-terminated polyester decreases, and the strength of the polyester resin decreases, so the number average molecular weight is preferably controlled to be less than 3,000. Specifically, the number average molecular weight of the non-crystalline carbon dioxide-based polyester diol segment can be 2,200, 2,400, 2,600, 2,800, 3,000, 3,200, 3,400, 3,600 or 3,800.

[0041] In one embodiment, the non-crystalline carbon dioxide-based polyester diol is preferably polypropylene carbonate diol (PPC), and the number average molecular weight is preferably 2,000-4,000. PPC is also a new type of biodegradable polymer material, which is a CO2-based diol derived from the third type of carbon source, and has fast degradation speed and high degradation rate.

[0042] In one embodiment, the non-crystalline carbon dioxide-based polyester diol has a hydroxyl value of 28.05-56.1 mgKOH / g.

[0043] In one embodiment, the polyester resin has a molecular weight of 20,000 to 60,000, preferably a number average molecular weight of 25,000 to 40,000, and more preferably 28,000 to 38,000. For the polyester resin, a molecular weight of 20,000 or more is preferred to achieve better cohesion, and a number average molecular weight of 60,000 or less is preferred to avoid degradation. The number average molecular weight of the polyester resin can be 22,000, 24,000, 26,000, 28,000, 30,000, 32,000, 34,000, 36,000, 38,000, 40,000, 42,000, 44,000, 46,000, 48,000, 50,000, 52,000, 54,000, 56,000, or 58,000.

[0044] The carboxyl-terminated polyester can be made of a new degradable material, and the non-crystalline carbon dioxide-based polyester diol is a new degradable material. The polyester resin prepared has good degradability.

[0045] The modified diol, the carboxyl-terminated polyester, and the non-crystalline carbon dioxide-based polyester diol are reacted in a certain proportion to obtain the polyester resin. The polyester resin contains carboxyl-terminated polyester segments, carbon dioxide-based polyester segments, and side chain segments. The modified diol segments contain side chains, which are introduced into the polyester resin to increase the branching degree of the polyester resin and enhance the activity of the overall molecular chain of the resin. The ester bonds in the side chains can provide a large number of hydrogen bonds, which can easily form hydrogen bonds with the bonding substrate to achieve good initial adhesion.

[0046] Regarding the second aspect of the present application, in one embodiment of the method for preparing the polyester resin, the carboxyl-terminated polyester, the non-crystalline carbon dioxide-based polyester diol, and the modified diol are added to a reaction kettle in a mass ratio of (10-20):(60-90):(5-20). After being heated to 130-150°C, a catalyst is added in an amount of 3wt‰-8wt‰ of the total mass of the carboxyl-terminated polyester, the non-crystalline carbon dioxide-based polyester diol, and the modified diol. After vacuum polycondensation for 3-4 hours, the polyester resin is obtained after cooling to room temperature. The vacuum degree is within 0.5 mmHg.

[0047] In one embodiment, the preparation of the modified diol includes the following steps:

[0048] The alcohol amine compound is added into an organic solvent, and an acrylic ester compound is added dropwise under inert gas protection, and then reacted at 10-40℃ for 1-50h, followed by liquid-liquid extraction, and removal of the organic solvent to obtain the self-made modified diol; wherein the molar ratio of the alcohol amine compound to the acrylic ester compound is (0.5-3):1.

[0049] In one embodiment, the alcohol amine compound is added into an organic solvent, and an acrylic ester compound is added dropwise under inert gas protection, and then reacted at 15-35℃ for 10-30h, followed by water washing, liquid-liquid extraction, and removal of the organic solvent by distillation under reduced pressure to obtain the modified diol; wherein the molar ratio of the alcohol amine compound to the acrylic ester compound is preferably (1-1.2):1; and the inert gas is preferably nitrogen and / or argon.

[0050] In one embodiment, the alcohol amine compound is one or more of diethanolamine, 2-amino-2-methyl-1,3-propanediol, 2-amino-1,3-propanediol, and 3-amino-1,2-propanediol.

[0051] In one embodiment, the acrylic ester compound is one or more of isooctyl acrylate, butyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, isooctyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, and hydroxypropyl methacrylate.

[0052] In one embodiment, the organic solvent is methanol, ethanol, or dimethylformamide.

[0053] In one embodiment, the catalyst is tetrabutyl titanate, tetraisopropyl titanate, or p-toluenesulfonic acid.

[0054] In one embodiment of the polyester-based pressure-sensitive adhesive according to the third aspect of the application, the polyester-based resin is preferably 60-99 parts, more preferably 80-99 parts, and can also be 90-99 parts or 95-99 parts. Since the polyester-based resin itself is easy to form hydrogen bonds with the bonding substrate and has good initial adhesion, the tackifying resin is optional, and the polyester-based pressure-sensitive adhesive has good cohesive properties, and the peel strength and tack of the pressure-sensitive adhesive can also be improved.

[0055] In one embodiment, the polyester-based pressure-sensitive adhesive can further include 1-50 parts of a tackifying resin, and the tackifying resin is one or more of natural rosin, hydrogenated rosin, disproportionated rosin, esterified rosin, C5 petroleum resin, C9 petroleum resin, and terpene resin.

[0056] In one embodiment, the additives include plasticizers, antioxidants, fillers, pigments, rheological additives, elastomers, light stabilizers, UV absorbers, and other auxiliaries such as drying agents, flow agents and flow control agents, surfactants or catalysts.

[0057] In one embodiment, the plasticizer is preferably 1-5 parts, and the antioxidant is preferably 0.1-0.2 parts.

[0058] The plasticizer is one or more of epoxidized soybean oil, linseed oil, castor oil, and palm oil.

[0059] In one embodiment, the antioxidant is one or more of tris(2,4-di-tert-butylphenyl) phosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, disteradecylthiodipropionate, and tetra-{3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid} pentaerythritol ester.

[0060] In one embodiment, the substrate is selected from the group consisting of paper, textile, nonwoven fabric, polymer, metal, and wood, and is preferably one of cellulose film, PET film, or paper.

[0061] In one embodiment, the pressure-sensitive adhesive product is an adhesive tape, an adhesive stick, or an adhesive roll.

[0062] In one embodiment, the pressure-sensitive adhesive product has a ball number of initial tack of 5 or more, a 180° peel strength of 6 N / 25 mm or more, a holding power of 84 hours or more, and a degradation rate of 87% or more.

[0063] In summary, the modified diol and the non-crystalline carbon dioxide-based polyester diol, carboxyl-terminated polyester are reacted in a certain proportion to obtain a polyester resin, which contains carboxyl-terminated polyester segments, non-crystalline carbon dioxide-based polyester segments and side chain segments, wherein the carboxyl-terminated polyester segments are a hard segment, which can provide the required cohesive strength of the polyester resin, the non-crystalline carbon dioxide-based polyester segments are a soft segment, which can ensure the elasticity of the polyester resin, the modified diol segments contain side chains, which are introduced into the polyester resin to increase the branching degree of the polyester resin, reduce the glass transition temperature of the polyester resin, enhance the activity of the overall molecular chain of the resin, and the ester bonds contained in the side chains can provide a large number of hydrogen bonds, which are easy to form hydrogen bond adhesion with the bonding substrate, and the initial adhesion is good. The polyester resin is prepared into a polyester pressure-sensitive adhesive, and tackifying resins can be selectively added or not added. If the tackifying resins are not added, the polyester pressure-sensitive adhesive also has strong cohesive properties, and there is no phase separation defect caused by poor compatibility of the tackifying resins with the base resin, so the peel strength and tackiness of the pressure-sensitive adhesive can be improved. And the preferred polyester resin also has good degradability.

[0064] Examples

[0065] The examples of the present application are only used for illustrative purposes, and should not be interpreted as limiting the present application.

[0066] For simplicity, only some numerical ranges are explicitly recited herein. However, any lower limit can be combined with any upper limit to form a range not explicitly recited; and any lower limit can be combined with other lower limits to form a range not explicitly recited, as can any upper limit with any other upper limit to form a range not explicitly recited. Furthermore, although not explicitly recited, every point or individual number within a range is included in that range. Thus, every point or individual number can serve as its own lower limit or upper limit to form a range not explicitly recited.

[0067] The foregoing summary of the application is not intended to describe every disclosed embodiment or implementation of the application. The following description more particularly exemplifies the illustrative embodiments. In the entire application, guidance is provided by a series of examples, which can be used in various combinations. In each instance, the list is merely representative and should not be construed as exhaustive.

[0068] The raw materials used in the following examples are all ordinary commercially available products unless otherwise specified.

[0069] The preparation process of the modified diol 1 in the following examples is as follows:

[0070] The diethanolamine is added into methanol, and the isooctyl acrylate is added dropwise under the protection of inert gas N2, and the reaction is carried out at 25±5℃ for 24h, then at least three water washing liquid-liquid extraction is carried out, and then the methanol is removed by reduced pressure distillation to obtain the modified diol 1; wherein the molar ratio of diethanolamine to isooctyl acrylate is 1.05:1.

[0071] The modified diol 1 is subjected to infrared testing, and the Nicolet iS50 Fourier transform infrared spectrometer of Thermo Fisher Scientific Company of the United States is used for testing, and the scanning wave number range is 400-4000cm -1 . The scanning number is 32 times. The sample to be tested is evenly coated on the dried KBr sheet, and the Fourier transform infrared spectrometer is used for scanning test analysis.

[0072] The infrared spectrum is shown in Figure 1, and from Figure 1, 3500 cm -1 is the stretching vibration peak of -OH, 2956 cm -1 and 2868 cm -1 are the symmetric and asymmetric stretching vibration peaks of methylene, 1750 cm -1 is the stretching vibration peak of -C=O, 1180 cm -1 is the stretching vibration peak of -C-N, indicating that the obtained product exists -OH, -CH2-, -C=O, -C-N, and the diethanolamine and isooctyl acrylate have undergone Michael addition reaction to obtain the target product.

[0073] The preparation process of the modified diol 2 described in the following examples is as follows:

[0074] The diethanolamine is added into methanol, and the isooctyl acrylate is added dropwise under the protection of inert gas N2, and the reaction is carried out at 25±5℃ for 24h, then at least three water washing liquid-liquid extraction is carried out, and then the methanol is removed by reduced pressure distillation to obtain the modified diol 1; wherein the molar ratio of diethanolamine to isooctyl acrylate is 1.05:1.

[0075] The preparation process of the modified diol 3 described in the following examples is as follows:

[0076] The diethanolamine is added into methanol, and the isooctyl acrylate is added dropwise under the protection of inert gas N2, and the reaction is carried out at 25±5℃ for 24h, then at least three water washing liquid-liquid extraction is carried out, and then the methanol is removed by reduced pressure distillation to obtain the modified diol 1; wherein the molar ratio of diethanolamine to isooctyl acrylate is 1.05:1.

[0077] The method for determining the acid value is as follows: a proper amount of sample is dissolved in 25 mL of chloroform solution, phenothalin is used as an indicator, and 0.1 mol / L potassium hydroxide / ethanol standard solution is used for titration until redness is observed and the color does not fade for 30 seconds. The acid value X of the sample is calculated according to formula (1):

[0078] wherein 56.1 is the molar mass of potassium hydroxide (g / mol); X represents the acid value of the sample (mgKOH / g); V1 is the milliliter number of the potassium hydroxide ethanol standard solution before titration (mL); V2 is the milliliter number of the potassium hydroxide ethanol standard solution after titration (mL), C is the concentration of the potassium hydroxide ethanol standard solution (mol / L), and m is the weight of the sample to be titrated (g).

[0079] The preparation process of the carboxyl-terminated polybutylene succinate 1 described in the following example is as follows:

[0080] 40 parts of 1,4-butanediol and 60 parts of succinic acid are put into a reaction kettle, then the temperature is raised to 165°C, 0.3 wt% of the catalyst tetrabutyl titanate based on the total mass of 1,4-butanediol and succinic acid is added, and the reaction is carried out for about 3 h, then the temperature is raised to 180°C and the reaction is carried out for about 1 h, then the temperature is raised to 205°C and vacuum polycondensation is carried out for 2 h, and the acid value is tested. The test result is 70.125 mgKOH / g (the number average molecular weight calculated is 1600, and the calculation formula is: , wherein y is the acid value), and the carboxyl-terminated polybutylene succinate 1 is obtained after cooling to room temperature.

[0081] The preparation process of the carboxyl-terminated polybutylene succinate 2 described in the following example is as follows:

[0082] 35 parts of 1,4-butanediol and 56 parts of succinic acid are put into a reaction kettle, then the temperature is raised to 160°C, 0.2 wt% of the catalyst tetrabutyl titanate based on the total mass of 1,4-butanediol and succinic acid is added, and the reaction is carried out for about 3 h, then the temperature is raised to 180°C and the reaction is carried out for about 1 h, then the temperature is raised to 200°C and vacuum polycondensation is carried out for 1 h, and the acid value is tested. The test result is 102 mgKOH / g (the number average molecular weight calculated is 1,100), and the carboxyl-terminated polybutylene succinate 2 is obtained after cooling to room temperature.

[0083] The preparation process of the carboxyl-terminated polybutylene succinate 3 described in the following example is as follows:

[0084] Put 45 parts of 1,4-butanediol and 65 parts of succinic acid into a reaction kettle, then warm up to 165℃, after adding 0.5wt% of catalyst tetrabutyl titanate based on the total mass of 1,4-butanediol and succinic acid, react for about 4h, then warm up to 180℃ and react for about 2h, then warm up to 220℃ and vacuum polycondensation for 4h, and test its acid ester. The acid value is 38.7 mgKOH / g (the number average molecular weight is calculated to be 2,900), and the carboxyl-terminated polybutylene succinate 3 is obtained after cooling to room temperature.

[0085] The polypropylene carbonate diols described in the following examples are all purchased from Huizhou Daya Bay Dazhi Fine Chemical Co., Ltd. (Guangzhou Branch).

[0086] The method for measuring the number average molecular weight of the following examples is as follows:

[0087] GPC test method: tested by using a GPC instrument of WATERS 1515 model of the United States Water Company, tetrahydrofuran (THF) as the mobile phase, flow rate 0.1 mL / min, monodisperse polystyrene as the molecular weight correction standard.

[0088] Example 1

[0089] A polyester resin is prepared as follows:

[0090] Put the carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight about 2,500), and the modified diol 1 in a mass ratio of 10:90:5 into a reaction kettle, warm up to 130-150℃, then add a catalyst at 5w‰ of the total mass of the carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol, and the modified diol 1, and polycondense for 4h under a vacuum degree of 0.5 mmHg or less, and then cool to room temperature to obtain a polyester resin, which has a molecular weight of about 32,000 as determined by GPC.

[0091] Example 2

[0092] A polyester resin is prepared as follows:

[0093] Put the carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight about 2,500), and the modified diol 1 in a mass ratio of 10:80:5 into a reaction kettle, warm up to 130-150℃, then add a catalyst at 5w‰ of the total mass of the carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol, and the modified diol 1, and polycondense for 4h under a vacuum degree of 0.5 mmHg or less, and then cool to room temperature to obtain a polyester resin, which has a molecular weight of about 31,000 as determined by GPC.

[0094] Example 3

[0095] A polyester resin is prepared by the following process:

[0096] Carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight of about 2,500), and the modified diol 1 are put into a reaction kettle in a mass ratio of 10:60:5. After being heated to 130-150°C, a catalyst is added in an amount of 3w‰ of the total mass of the carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol, and the modified diol. After polycondensation for 4h under a vacuum degree of 0.5 mmHg, the polyester resin is obtained after cooling to room temperature. The molecular weight is about 28,000 as determined by GPC.

[0097] Example 4

[0098] A polyester resin is prepared by the following process:

[0099] Carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight of about 2,500), and the modified diol 1 are put into a reaction kettle in a mass ratio of 15:90:5. After being heated to 130-150°C, a catalyst is added in an amount of 5w‰ of the total mass of the carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol, and the modified diol 1. After polycondensation for 4h under a vacuum degree of 0.5 mmHg, the polyester resin is obtained after cooling to room temperature. The molecular weight is about 33,000 as determined by GPC. Example 5

[0100] A polyester resin is prepared by the following process:

[0101] Carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight of about 2,500), and the modified diol 1 are put into a reaction kettle in a mass ratio of 20:90:5. After being heated to 130-150°C, a catalyst is added in an amount of 5w‰ of the total mass of the carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol, and the modified diol 1. After polycondensation for 4h under a vacuum degree of 0.5 mmHg, the polyester resin is obtained after cooling to room temperature. The molecular weight is about 35,000 as determined by GPC.

[0102] Example 6

[0103] A polyester resin is prepared by the following process:

[0104] Carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight about 2,500), the modified diol 1 are put into the reaction kettle according to mass fraction 10:90:10, after heating to 130-150℃, 5w‰ of the total mass of catalyst of carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol and the modified diol 1 is added, and after polycondensation for 4h under vacuum degree within 0.5mmHg, it is cooled to room temperature to obtain polyester resin, and the molecular weight is about 33,000 by GPC determination. Example 7

[0105] A polyester resin is prepared as follows:

[0106] Carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight about 2,500), the modified diol 1 are put into the reaction kettle according to mass fraction 10:90:20, after heating to 130-150℃, 8w‰ of the total mass of catalyst of carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol and the modified diol 1 is added, and after polycondensation for 3h under vacuum degree within 0.5mmHg, it is cooled to room temperature to obtain polyester resin, and the molecular weight is about 30,000 by GPC determination.

[0107] Example 8

[0108] A polyester resin is prepared as follows:

[0109] Carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight about 2,500), the modified diol 2 are put into the reaction kettle according to mass fraction 10:90:5, after heating to 130-150℃, 5w‰ of the total mass of catalyst of carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol and the modified diol 2 is added, and after polycondensation for 4h under vacuum degree within 0.5mmHg, it is cooled to room temperature to obtain polyester resin, and the molecular weight is about 32,000 by GPC determination. Example 9

[0110] A polyester resin is prepared as follows:

[0111] Carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight about 2,500), the modified diol 3 are put into the reaction kettle according to mass fraction 10:90:5, after heating to 130-150℃, 5w‰ of the total mass of catalyst of carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol and the modified diol 3 is added, and after polycondensation for 4h under vacuum degree within 0.5mmHg, it is cooled to room temperature to obtain polyester resin, and the molecular weight is about 32,000 by GPC determination.

[0112] Example 10

[0113] A polyester resin is prepared as follows:

[0114] Carboxyl-terminated polybutylene succinate 2, polypropylene carbonate diol (molecular weight about 2,500), and the modified diol 1 are put into a reaction kettle in a mass ratio of 10:90:5, and after being heated to 130-150°C, a catalyst is added in an amount of 5 w‰ of the total mass of carboxyl-terminated polybutylene succinate 2, polypropylene carbonate diol, and the modified diol 1. After polycondensation for 4 h under a vacuum degree of 0.5 mmHg, the polyester resin is obtained after cooling to room temperature, and the molecular weight is about 29,000 as determined by GPC. Example 11

[0115] A polyester resin is prepared as follows:

[0116] Carboxyl-terminated polybutylene succinate 3, polypropylene carbonate diol (molecular weight about 2,500), and the modified diol 1 are put into a reaction kettle in a mass ratio of 10:90:5, and after being heated to 130-150°C, a catalyst is added in an amount of 5 w‰ of the total mass of carboxyl-terminated polybutylene succinate 3, polypropylene carbonate diol, and the modified diol 1. After polycondensation for 4 h under a vacuum degree of 0.5 mmHg, the polyester resin is obtained after cooling to room temperature, and the molecular weight is about 38,000 as determined by GPC.

[0117] Example 12

[0118] A polyester resin is prepared as follows:

[0119] Carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight about 2,000), and the modified diol 1 are put into a reaction kettle in a mass ratio of 10:90:5, and after being heated to 130-150°C, a catalyst is added in an amount of 5 w‰ of the total mass of carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol, and the modified diol 1. After polycondensation for 4 h under a vacuum degree of 0.5 mmHg, the polyester resin is obtained after cooling to room temperature, and the molecular weight is about 30,000 as determined by GPC.

[0120] Example 13

[0121] A polyester resin is prepared as follows:

[0122] The carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol (molecular weight of about 4,000), and the modified diol 1 were put into a reaction kettle in a mass ratio of 10:90:5, heated to 130-150°C, and then 5 w‰ of a catalyst was added, and the total mass of the carboxyl-terminated polybutylene succinate 1, polypropylene carbonate diol, and the modified diol 1. After polycondensation for 4 h under a vacuum degree of 0.5 mmHg, the temperature was cooled to room temperature to obtain a polyester resin with a molecular weight of about 35,000, as determined by GPC.

[0123] Examples 14 to 26

[0124] A polyester pressure-sensitive adhesive was prepared as follows:

[0125] The polyester resins described in Examples 1 to 13 were respectively formulated into polyester pressure-sensitive adhesives, and the specific formulations and preparation methods were as follows:

[0126] 95 parts of the polyester resin, 5 parts of epoxy soybean oil, and 0.15 parts of the antioxidant tris(2,4-di-tert-butylphenyl) phosphite were stirred at 130°C for 3 h, and then an appropriate amount of chloroform solution was added after cooling to room temperature to obtain a pressure-sensitive adhesive solution with a solid content of 20 wt%;

[0127] The pressure-sensitive adhesive solution was coated on a PET film by a coating machine, and the chloroform was evaporated after incubation at 80°C for 10 min. The thickness of the pressure-sensitive adhesive layer of the obtained pressure-sensitive adhesive tape was about 15 μm.

[0128] Among them, the polyester pressure-sensitive adhesive used in Example 14 is the polyester pressure-sensitive adhesive described in Example 1, the polyester pressure-sensitive adhesive used in Example 15 is the polyester pressure-sensitive adhesive described in Example 2, the polyester pressure-sensitive adhesive used in Example 16 is the polyester pressure-sensitive adhesive described in Example 3, and so on, and the polyester pressure-sensitive adhesive used in Example 26 is the polyester pressure-sensitive adhesive described in Example 13. Example 27

[0129] A polyester pressure-sensitive adhesive was prepared as follows:

[0130] 97 parts of the polyester resin described in Example 1, 3 parts of epoxy soybean oil, and 0.1 parts of the antioxidant tris(2,4-di-tert-butylphenyl) phosphite were stirred at 130°C for 3 h, and then an appropriate amount of chloroform solution was added after cooling to room temperature to obtain a degradable pressure-sensitive adhesive with a solid content of 20 wt%.

[0131] The pressure-sensitive adhesive solution was coated on a PET film by a coating machine, and the chloroform was evaporated after incubation at 80°C for 10 min. The thickness of the pressure-sensitive adhesive layer of the obtained pressure-sensitive adhesive tape was about 15 μm.

[0132] Example 28

[0133] The polyester pressure-sensitive adhesive is prepared as follows:

[0134] The polyester resin described in Example 1, 99 parts, 1 part of epoxy soybean oil, and 0.1 part of antioxidant tris (2, 4-di-tert-butylphenyl) phosphite are stirred at 130°C for 3h, and after cooling to room temperature, a proper amount of chloroform solution is added to obtain a degradable pressure-sensitive adhesive with a solid content of 20wt%;

[0135] The pressure-sensitive adhesive solution is coated on a PET film by a coating machine, and after being kept at 80°C for 10min, the chloroform is evaporated, and the thickness of the pressure-sensitive adhesive layer of the obtained pressure-sensitive adhesive tape is about 15μm.

[0136] The polyester pressure-sensitive adhesives described in Examples 14 to 28 are subjected to performance tests, and the test items and methods are as follows:

[0137] (1) Initial adhesion: tested according to the provisions of Method A in GB / T 4852-2002, with the inclined plane inclined at 30°.

[0138] (2) 180° peel strength: tested according to the provisions of GB / T 2792.

[0139] (3) Holding adhesion: tested according to the provisions of Method A in GB / T 4851-2014, with the width of the degradable adhesive tape sample being 25mm, the length of the adhesive surface of the sample adhered to the steel plate being (12±0.5mm), and the weight of the weight being (1000±5g).

[0140] (4) Biodegradation rate: tested according to the provisions of GB / T 19277.1.

[0141] The test results are shown in Table 1.

[0142] Table 1

[0143] Obviously, the above examples of the present application are only examples for clearly illustrating the technical solutions of the present application, and are not intended to limit the specific embodiments of the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application should be included in the protection scope of the claims of the present application.

Claims

1. A polyester-based resin, characterized by, The polyester resin comprises a carboxyl-terminated polyester, a non-crystalline carbon dioxide-based polyester diol and a modified diol, and the mass ratio of the carboxyl-terminated polyester, the non-crystalline carbon dioxide-based polyester diol and the modified diol is (10-30):(50-99):(2-30); wherein the modified diol has a structural formula as shown in Formula 1, Formula 2 or Formula 3: Formula 1; Formula 2; Formula 3; wherein: R1 is C1-12 alkyl; R2 is C1-12 alkyl; R3 is C1-12 alkyl; R4 is H or C1-12 alkyl; R5 is C1-12 alkyl.

2. The polyester-based resin according to claim 1, characterized by The mass fraction of the carboxyl-terminated polyester is 10-25, the mass fraction of the non-crystalline carbon dioxide-based polyester diol is 60-90, and the mass fraction of the modified diol is 4-25, and the molecular weight of the polyester resin is 20000-60000.

3. The polyester-based resin according to claim 1 or 2, characterized by The mass fraction of the carboxyl-terminated polyester is 10-20, the mass fraction of the non-crystalline carbon dioxide-based polyester diol is 55-95, and the mass fraction of the modified diol is 5-20, and the molecular weight of the polyester resin is 25000-40000, more preferably 28000-38000.

4. The polyester-based resin according to any one of claims 1 to 3, characterized in that, The number average molecular weight of the carboxyl-terminated polyester is 1000-3000, the carboxyl-terminated polyester is polymerized from C3-7 diacid and C3-7 diol, and the number average molecular weight of the non-crystalline carbon dioxide-based polyester diol is 2000-4000.

5. The polyester-based resin according to any one of claims 1 to 4, characterized in that, The carboxyl-terminated polyester is carboxyl-terminated polybutylene succinate, and the hydroxyl value is 37.4-112 mgKOH / g, and the non-crystalline carbon dioxide-based polyester diol is polypropylene carbonate diol.

6. A method for producing the polyester-based resin as claimed in any one of claims 1 to 5, characterized by, The method comprises the following steps: The carboxyl-terminated polyester, the non-crystalline carbon dioxide-based polyester diol and the modified diol are put into a reaction kettle in a mass ratio of (10-30):(50-99):(2-30), heated to 100-180℃, and then 1‰-2% of the total mass of the carboxyl-terminated polyester, the non-crystalline carbon dioxide-based polyester diol and the modified diol is added as a catalyst, vacuum polycondensation is performed, and then cooling is performed to obtain the polyester resin.

7. The production method according to claim 6, wherein The carboxyl-terminated polyester, the non-crystalline carbon dioxide-based polyester diol and the modified diol are put into a reaction kettle in a mass ratio of (10-20):(60-90):(5-20), heated to 130-150℃, and then 3wt‰-8wt‰ of the total mass of the carboxyl-terminated polyester, the non-crystalline carbon dioxide-based polyester diol and the modified diol is added as a catalyst, vacuum polycondensation is performed under a vacuum degree of 0.5mmHg for 3-4h, and then cooling is performed to room temperature to obtain a polyester pressure-sensitive adhesive resin; the catalyst is tetrabutyl titanate, tetraisopropyl titanate or p-toluenesulfonic acid.

8. The production method according to claim 6 or 7, characterized by, The preparation of the modified dihydric alcohol comprises the following steps: adding an alcohol amine compound into an organic solvent, adding dropwise an acrylate compound under inert gas protection, reacting at 10-40℃ for 1-50h, then performing liquid-liquid extraction, removing the organic solvent, and obtaining the self-prepared modified dihydric alcohol; wherein the molar ratio of the alcohol amine compound to the acrylate compound is (0.5-3):

1.

9. The method for producing a polyester-based resin according to claim 8, characterized by, The alcohol amine compound is one or more of diethanolamine, 2-amino-2-methyl-1,3-propanediol, 2-amino-1,3-propanediol, and 3-amino-1,2-propanediol, the acrylate compound is one or more of isooctyl acrylate, butyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, isooctyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, and hydroxypropyl methacrylate, and the organic solvent is methanol, ethanol, or dimethylformamide.

10. The production method according to claim 8 or 9, characterized by, The reaction is performed at 20-30℃ for 2-30h, then liquid-liquid extraction is performed three times or more, and the organic solvent is removed by distillation under reduced pressure, and the molar ratio of the alcohol amine compound to the acrylate compound is (1-1.2):

1.

11. A polyester-based pressure sensitive adhesive, characterized by, The polyester resin comprises the following components in parts by mass: 50-99 parts of the polyester resin according to any one of claims 1-5, or prepared by the method according to any one of claims 6-10; and 0.1-10 parts of an additive.

12. The polyester-based pressure sensitive adhesive according to claim 11, wherein, The polyester resin is 60-99 parts, or 80-99 parts, or 90-99 parts, or 95-99 parts; and the additive comprises 1-5 parts of a plasticizer and 0.1-0.2 parts of an antioxidant.

13. The polyester-based pressure sensitive adhesive according to claim 12, wherein The plasticizer is one or more of epoxidized soybean oil, flaxseed oil, castor oil, and palm oil, and the antioxidant is one or more of tris(2,4-di-tert-butylphenyl)phosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, dilauryl thiodipropionate, and tetra(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) pentaerythritol ester.

14. A pressure sensitive adhesive product comprising a substrate and a pressure sensitive adhesive layer adhered to the substrate, characterized in that, The pressure-sensitive adhesive layer comprises the polyester pressure-sensitive adhesive according to any one of claims 11-13.

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