High-hydrolysis-resistance temperature-sensitive polyester sponge as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of foaming materials, and particularly relates to high-hydrolysis-resistance temperature-sensitive polyester sponge as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out reaction on a component A and a component B, wherein the component A comprises polyester polyol, a foaming agent, a foaming catalyst, a surfactant and an opening agent; the component A comprises polyester polyol, the component B comprises isocyanate or an isocyanate mixture, the polyester polyol at least comprises polyester polyol a containing a benzene ring, and the functionality of the polyester polyol a containing the benzene ring is 2.1-2.5. Compared with the existing temperature-sensitive polyester sponge on the market, the high-hydrolysis-resistance temperature-sensitive polyester sponge provided by the invention has more excellent hydrolysis resistance, higher hardness, more obvious temperature-sensitive effect and higher tear strength.

Description

Technical Field

[0001] This invention belongs to the field of foaming material technology, specifically relating to a high hydrolysis-resistant temperature-sensitive polyester sponge, its preparation method, and its application. Background Technology

[0002] Taking kitchen cleaning as an example, people commonly use tools such as rags, steel wool, loofahs, and brushes of various materials, along with detergents and strong degreasers, to clean grime. However, it's difficult to clean completely. Steel wool, due to its high metal hardness, can scratch ceramic countertops and dishes, and food residue and grime can get inside. It's also difficult to dry and prone to bacterial growth. Loofahs, on the other hand, have low hardness and friction, making them difficult to clean thoroughly, and food residue and grime can get inside, leading to bacterial growth. Rags are also soft, difficult to clean, slow to dry, and prone to bacterial growth. Brushes of various materials also generally have the problem of food residue and grime getting inside, being difficult to dry, and easily breeding bacteria. In light of this, there is an urgent market demand for temperature-sensitive (hard at room temperature, soft at high temperatures) sponges, and some temperature-sensitive sponges have emerged, mainly categorized by material as polyether-type and polyester-type temperature-sensitive sponges.

[0003] Polyether-based temperature-sensitive sponges offer advantages in design and manufacturing compared to polyester-based sponges due to their greater flexibility in raw materials and formulation. However, they also suffer from drawbacks such as shorter lifespan due to poorer mechanical properties. Their higher open-cell ratio allows food residue, dirt, and water to enter the sponge during use, and they are difficult to dry, leading to bacterial growth. These drawbacks do not meet the requirements of end consumers. Polyester-based temperature-sensitive sponges, on the other hand, have higher crystallinity and a higher density of hydrogen bonds, resulting in better mechanical properties. They also have a higher closed-cell ratio, eliminating the problems of food residue and dirt entering the sponge and the difficulty in drying, making them ideal for use as household cleaning tools.

[0004] Patent CN202311294719 describes a method for preparing temperature-sensitive polyester sponges by mixing and foaming rigid and flexible foam polyester polyols to create semi-rigid foam. The temperature-sensitive effect of the polyester sponge is achieved through the dynamic reversibility of hydrogen bonds (high-temperature dissociation and low-temperature reformation). A two-step foaming process is used, first prepolymerizing a high-hydroxyl-value rigid foam polyester polyol to prepare an NCO-terminated prepolymer, and then mixing the NCO-terminated prepolymer with a flexible foam polyester polyol. This solves the problem of matching the reactivity of the two types of polyester polyols due to their large differences in hydroxyl values. The introduction of fluorinated hydroxyl silicone oil improves the sponge's hydrophobicity; the use of polyester polyols derived from the condensation of ethylene glycol, 3-methyl-1,5-pentanediol, and adipic acid as the starting agent for flexible foam further enhances the sponge's hydrophobicity through steric hindrance by utilizing the presence of side methyl groups. Other techniques are used to improve the sponge's softness and tear resistance. However, the sponge prepared using this patented method still has the following problems:

[0005] 1. The hydrophobic properties of fluorinated hydroxyl silicone oil and the steric hindrance effect of the side methyl groups in the molecular structure of soft foam polyester polyol can indeed improve the hydrophobicity of sponge, but the effect on improving the hydrolysis resistance of sponge during use (the sponge enters the sponge interior and fully contacts the sponge due to compression and capillary effect of the foam pores) is limited, and the hydrolysis resistance of the resulting sponge is still poor.

[0006] 2. The processing tolerance of the obtained sponge is narrow, and shrinkage is prone to occur, resulting in a low yield rate. This is because the high hydroxyl value polyester polyol A in the patent has a short molecular chain, which makes the density of hard segments in the sponge high and the strength of the foam membrane high, which easily leads to the closure of the sponge. The 2.5 ~ 3 functionality polyester polyol B has a high functionality, which makes the crosslinking density in the sponge high, which easily leads to the closure of the sponge.

[0007] 3. Adding small molecule amine crosslinking agents to prepolymers to increase the degree of crosslinking in hard segments can indeed improve the tear strength of sponges, but the increase is limited, and the resulting sponges still have poor tear strength.

[0008] Its hardness at room temperature is relatively low, making it unsuitable for cleaning dirt in a low-temperature, hard state; and the difference in hardness between high and low temperatures is not significant enough, resulting in poor temperature sensing effect. Summary of the Invention

[0009] To address the problems that need to be solved in the existing technology, the present invention proposes the following design ideas:

[0010] 1) To address the issue of narrow tolerance in the processing technology of temperature-sensitive sponge in patent CN202311294719, which easily leads to shrinkage and low yield, the solution is to add a suitable cell opener to the formula. The addition of the cell opener can increase the pore size and openness of the sponge, which is beneficial for preparing temperature-sensitive polyester sponge with larger pores. However, the amount of cell opener added should not be too high or too low. Too high an amount can easily cause the foam to collapse during foaming, while too low an amount will result in insufficient openness and easy shrinkage.

[0011] 2) Addressing the issues of low hardness, poor temperature sensing effect, poor tear strength, and poor hydrolysis resistance of temperature-sensitive sponge at room temperature as described in patent CN202311294719, and the problem of sponge collapse during foaming caused by the introduction of a cell-opening agent, a method is adopted to synthesize a special polyester polyol for temperature-sensitive polyester sponge. A benzene ring structure and higher functionality are introduced into the molecular structure of the special polyester polyol. The high hardness and high glass transition temperature characteristics of the benzene ring structure solve the problems of low hardness and poor temperature sensing effect of the temperature-sensitive sponge. The high tear strength characteristics of the benzene ring structure and the high crosslinking density in the sponge molecular structure due to the high functionality of the polyester polyol solve the problem of poor tear strength. The benzene ring structure with greater steric hindrance compared to the side methyl group improves the problem of poor hydrolysis resistance. The functionality of the special polyester polyol should not be too high, otherwise it will easily lead to a high closed-cell rate during foaming, which will conflict with the introduction of the open-cell agent, resulting in a lower process tolerance during foaming of the sponge. It is easy to either collapse or shrink, or even both collapse and shrinkage in severe cases. The process tolerance is broadened by using a combination of low-functionality polyester polyol for foaming.

[0012] 3) Regarding the poor hydrolysis resistance caused by the short carbon chain of adipic acid in the polyester polyol with an adipic acid structure used in patent CN202311294719, resulting in an excessively high ester group density, this problem is solved by replacing part of the adipic acid with a long-chain diacid. The relatively lower ester group density of the long-chain diacid fundamentally improves the hydrolysis resistance of the sponge. Simultaneously, the molecular chain strength of the long-chain diacid is much lower than that of the short-chain adipic acid. The reduced foam membrane strength and tendency for the sponge to open and collapse due to the introduction of long-chain diacids can be neutralized by the characteristics of excessively high foam membrane strength, excessively high closed-cell rate, and easy shrinkage caused by the introduction of a rigid benzene ring structure and high functionality in approach 2). This allows the problems of poor hydrolysis resistance, poor tear strength, low hardness, and poor temperature sensitivity of polyester sponges to be solved at the molecular structure level, while ensuring the tolerance of the foaming process.

[0013] A method for preparing a highly hydrolysis-resistant, temperature-sensitive polyester sponge includes the following steps: reacting component A and component B, wherein component A comprises polyester polyol, foaming agent, foaming catalyst, surfactant, and cell opener; and component B comprises isocyanate or a mixture of isocyanates, wherein:

[0014] The polyester polyol includes at least a polyester polyol a containing a benzene ring, wherein the functionality of the polyester polyol a containing a benzene ring is 2.1 to 2.5.

[0015] The high hydrolysis-resistant temperature-sensitive polyester sponge provided by this invention has the characteristics of being a rigid foam at 30°C and lower temperatures and a soft foam at 50°C and higher temperatures. It also has extremely excellent hydrolysis resistance, relatively large pore size and low open cell ratio (air permeability), making it very suitable for use as a household cleaning tool.

[0016] Specifically, the polyester polyol a containing a benzene ring is obtained by reacting an acid or anhydride, a diol, and a synthesis catalyst under heating conditions, wherein:

[0017] At least one of the said acids or anhydrides contains a benzene ring;

[0018] The diol includes one or a mixture of two linear diols or meso diols;

[0019] The synthesis catalyst is one or more of stannous octoate, dibutyltin laurate, tetrabutyl titanate, or tetraisopropyl titanate, and is used in an amount of 0.03%-0.1% of the weight of the diol. Preferably, it is tetrabutyl titanate.

[0020] In the acid or anhydride, the carbon chain length of the acid is greater than or equal to six carbons.

[0021] Specifically:

[0022] The acid or anhydride is selected from one or more of the following: bis(2,3',4')-di(2,3',4')-diphenyltetracarboxylic anhydride; octanoic acid, sebacic acid, phthalic anhydride, isophthalic anhydride, 2,2-bis[4-(3,4-phenoxyphenyl)]propane dianhydride, or 2,3,3',4'-biphenyltetracarboxylic dianhydride.

[0023] The linear diol is one or more of ethylene glycol (EG), diethylene glycol (DEG), 1,4-butanediol (BDO), 1,6-hexanediol (HDO), and triethylene glycol (TEG);

[0024] The body-type diol is one or more of neopentyl glycol (NPG), 2-methyl-1,3-propanediol (MPO), 2-methyl-2,4-pentanediol (2-MPD), 3-methyl-1,5-pentanediol (3-MPD), butyl ethyl propylene glycol (BEPD), and diethyl pentanediol.

[0025] Preferred:

[0026] The acid or anhydride is a mixture of adipic acid, sebacic acid and 2,3,3',4'-biphenyltetracarboxylic dianhydride; the weight ratio of adipic acid, sebacic acid and 2,3,3',4'-biphenyltetracarboxylic dianhydride is (50 ~ 65):(15 ~ 35):(3 ~ 10);

[0027] The diol is a mixture of diethylene glycol (DEG) and neopentyl glycol (NPG), with a weight ratio of neopentyl glycol (NPG) to diethylene glycol of (3:7) to (7:3).

[0028] Specifically:

[0029] The polyester polyols include polyester polyol a containing benzene rings and polyester polyol b;

[0030] The polyester polyol a containing benzene ring has a hydroxyl value of 150 ~ 170 mgKOH / g and a viscosity of 10000 ~ 30000 mPa•s / 25℃;

[0031] The polyester polyol b has a weight-average molecular weight of 2000-2500 g / mol, a functionality of 2.0, and a viscosity of 7000-20000 mPa•s / 25℃.

[0032] The weight ratio of the polyester polyol a containing benzene rings and the polyester polyol b is (8:2) ~ (6:4).

[0033] Specifically:

[0034] The foaming catalyst is one or more of a tertiary amine catalyst or an organometallic catalyst, and its addition amount is 0.5wt% to 1wt% of the polyester polyol.

[0035] The surfactant is a polyether-modified silicone surfactant, and its addition amount is 1wt% to 2wt% of the amount of polyester polyol added.

[0036] The amount of the cell opener added is 0.03 wt% to 0.3 wt% of the amount of the polyester polyol added;

[0037] The foaming agent is water, and the amount used is adjusted according to the product density.

[0038] Component B includes one or more of toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), or crude MDI, and its addition amount is weighed according to a formulation index of 1.10-1.20 (preferably 1.15).

[0039] Specifically, the preparation method of the polyester polyol a containing benzene rings includes the following steps: adding acid or acid anhydride, diol, and synthesis catalyst into a reaction vessel, and heating to 105-115℃ (preferably 110℃) while stirring and mixing under inert gas protection, and stirring and reacting at 105-115℃ (preferably 110℃) for 1-3 hours (preferably 2 hours); then stirring and reacting at 140-150℃ (preferably 145℃), 175-185℃ (preferably 180℃), 210-220℃ (preferably 215℃), and 245-255℃ (preferably 250℃) for 1-3 hours (preferably 2 hours) respectively to obtain the polyester polyol a containing benzene rings.

[0040] Subsequently, the reaction was carried out at 250°C while a vacuum was applied to remove the condensation water and entrained small molecule polyols generated in the reactants. After 2 hours, samples were taken to test the acid value and hydroxyl value, and the tests were conducted every half hour until the acid value was less than 1.0 mgKOH / g and the hydroxyl value reached the theoretical hydroxyl value of 160±10 mgKOH / g, indicating that the polyester polyol used in this invention had been successfully synthesized.

[0041] Specifically, it includes the following steps:

[0042] 1) Prepare the raw materials of component A according to the proportion, and stir at a speed of 750-850 RPM (preferably 800 RPM) for 55-65 seconds (preferably 60 seconds) until they are evenly mixed;

[0043] 2) Weigh component B and component A, and stir them with a mixer at a speed of 1400-1600 RPM (preferably 1500 RPM) for 4-6 seconds (preferably 5 seconds) to obtain a mixture. Then immediately pour the mixture into a mold with a built-in release film to foam and obtain a sponge foam.

[0044] 3) The obtained foam is then left to stand and mature for 45-50 hours (preferably 48 hours) to obtain a fully matured, highly hydrolysis-resistant, temperature-sensitive polyester sponge.

[0045] The present invention also provides a highly hydrolysis-resistant temperature-sensitive polyester sponge prepared according to the above preparation method.

[0046] This invention also provides applications of highly hydrolysis-resistant temperature-sensitive polyester sponges:

[0047] Used as rigid foam at 30℃;

[0048] Alternatively, it can be used as a soft foam at temperatures above 50°C.

[0049] The beneficial effects of this invention are as follows:

[0050] 1) The high hydrolysis resistant temperature-sensitive polyester sponge provided by the present invention has better hydrolysis resistance, higher hardness, more significant temperature-sensitive effect and higher tear resistance than existing temperature-sensitive polyester sponges on the market.

[0051] 2) The high hydrolysis resistant temperature-sensitive polyester sponge provided by this invention has a larger pore size and a lower open porosity (air permeability);

[0052] 3) The high hydrolysis resistance temperature-sensitive polyester sponge provided by the present invention has the characteristics of being a rigid foam at 30°C and lower temperatures and a soft foam at 50°C and higher temperatures. It also has extremely excellent hydrolysis resistance, relatively large pore size and low open cell ratio (air permeability), making it very suitable for use as a household cleaning tool. Detailed Implementation

[0053] The principles and features of the present invention are described below. The embodiments given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0054] Unless otherwise specified, the test methods used in the embodiments are existing methods; the materials and reagents used are commercially available unless otherwise specified.

[0055] Example 1

[0056] The preparation of highly hydrolysis-resistant temperature-sensitive polyester sponge includes the following steps:

[0057] 1) Preparation of special polyester polyols

[0058] Weigh 2 kg of acid / anhydride according to a mass ratio of adipic acid: sebacic acid: 2,3,3',4'-biphenyltetracarboxylic dianhydride of 60:35:5. Weigh neopentyl glycol and diethylene glycol according to a molar ratio of hydroxyl to carboxyl groups of 1.2:1, wherein the mass ratio of neopentyl glycol to diethylene glycol is 4:6. Weigh tetrabutyl titanate catalyst according to a mass ratio of 0.1%:1 for the diol (neopentyl glycol and diethylene glycol). Add the acid or anhydride, diol, and catalyst to the reaction vessel. Under inert gas protection, stir and mix while heating to 110°C, and react at 110°C for 2 h. Subsequently, react at 145°C, 180°C, 215°C, and 250°C for 2 h each. During this period, the condensation water produced by the esterification reaction is cooled and collected through a serpentine condenser.

[0059] Subsequently, the reaction was carried out at 250℃ while a vacuum was applied to remove the condensation water and entrained small-molecule polyols generated in the reactants. After 2 hours, samples were taken to test the acid value and hydroxyl value, with tests performed every half hour. The final special polyester polyol was found to have an acid value of 0.67 mgKOH / g, a hydroxyl value of 159.55 mgKOH / g, and a viscosity of 28643 mPa•s / 25℃. The functionality of this special polyester polyol was 2.5.

[0060] 2) Preparation of high hydrolysis resistant temperature-sensitive polyester sponge

[0061] Weigh 160g of the special polyester polyol a prepared in step 1), 40g of polyester polyol XCP-2000PM from Asahikawa Chemical (Suzhou) Co., Ltd., 4.25g of water, 1g of DM70 amine catalyst from HUNTSMAN, 0.3g of tin catalyst EF, 2g of TEGOSTABE B8335 surfactant from Evonik Chemical, and 0.4g of K757 cell opener from Nanjing Zhong'an Chemical Co., Ltd., and stir at 800RPM for 60s. After mixing evenly, obtain component A. Weigh 96.49g of toluene diisocyanate TDI-65 from Wanhua Chemical as component B. Stir component B and component A together at 1500RPM for 5s to obtain a mixture. Immediately pour the mixture into a mold with a built-in release film to foam and obtain a sponge foam. Then, let the obtained foam stand and mature for 48 hours to obtain a fully matured, highly hydrolysis-resistant, temperature-sensitive polyester sponge.

[0062] Example 2

[0063] The difference between Example 2 and Example 1 is that in step 2) of the preparation of the high hydrolysis resistant temperature-sensitive polyester sponge, the amount of special polyester polyol a added in component A is 120g, the amount of polyester polyol b added is 80g, and the amount of TDI-65 added is 89.13g. The rest is the same as in Example 1.

[0064] Example 3

[0065] The difference between Example 3 and Example 1 is that in step 2) of the preparation of the high hydrolysis resistant temperature-sensitive polyester sponge, the opening agent K757 in component A is not added, while the rest is the same as in Example 1.

[0066] Example 4

[0067] The difference between Example 4 and Example 1 is that in step 2) of the preparation of the high hydrolysis resistant temperature-sensitive polyester sponge, the amount of pore-opening agent K757 added in component A is 0.7g, while the rest is the same as in Example 1.

[0068] Example 5

[0069] The difference between Example 5 and Example 1 is as follows:

[0070] In step 1), during the preparation of the special polyester polyol, sebacic acid is removed, and only adipic acid and 2,3,3',4'-biphenyltetracarboxylic dianhydride are used. The weight ratio of adipic acid to 2,3,3',4'-biphenyltetracarboxylic dianhydride is 95:5.

[0071] In step 2), the amount of TDI-65 added in the preparation of the high hydrolysis resistant temperature-sensitive polyester sponge is 96.27g.

[0072] The rest is the same as in Example 1.

[0073] The final special polyester polyol was tested and found to have an acid value of 0.74 mgKOH / g, a hydroxyl value of 158.78 mgKOH / g, and a viscosity of 19561 mPa•s / 25℃.

[0074] Example 6

[0075] The difference between Example 6 and Example 1 is:

[0076] In step 1), during the preparation of the special polyester polyol, only two acids / anhydrides are used: adipic acid, sebacic acid, and 2,3,3',4'-biphenyltetracarboxylic dianhydride.

[0077] In step 2) the preparation of high hydrolysis resistant temperature-sensitive polyester sponge, the amount of TDI-65 added is 96.78g;

[0078] The rest is the same as in Example 1.

[0079] The final product, a special polyester polyol, was tested and found to have an acid value of 0.51 mgKOH / g, a hydroxyl value of 160.57 mgKOH / g, and a viscosity of 11463 mPa•s / 25℃. The functionality of this special polyester polyol is 2.0.

[0080] Comparative Example 1

[0081] According to the method provided in patent CN202311294719, the design density is 40 kg / m³ 3 The prepared temperature-sensitive polyester sponge.

[0082] Comparative Example 2

[0083] The Scrub Daddy smiley face cleaning sponge is currently the highest-performing imported temperature-sensitive polyester sponge on the market.

[0084] The physical property test results of the sponges prepared in Examples 1 to 6 and Comparative Examples 1 and 2 are shown in Table 1.

[0085] The hydrolysis resistance test method was as follows: An Amana TandemNFW 5800 DW washing machine was used with the parameters set to "Heavy Duty" mode (spin speed approximately 800 rpm) and the temperature knob set to "Hot" (water temperature approximately 60-70°C). During the wash cycle, 6±0.5g of Dawn Platinum dish soap was added, along with 15 rigid PVC balls weighing 110g each and with a diameter of 66.5mm to simulate mechanical friction load. The number of samples used in the wash test was 7-15; if insufficient, blank samples were used to supplement to 7. After washing, the samples were dried in a 70°C laboratory oven for 12±1 hours. After drying, the samples were placed at 23±2°C and 50±5% relative humidity for 1 hour to return to the test environment; this constituted one round of hydrolysis testing. The washing and drying cycles were then repeated for a total of 12 rounds of hydrolysis testing. Finally, the weight loss rate was calculated according to the formula "weight loss rate = (initial mass - final mass) * 100 / initial mass".

[0086] Table 1. Test results of the physical properties of temperature-sensitive polyester sponge

[0087] Test Project Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Foaming phenomenon normal normal shrink Collapsed bubble normal normal There is a very high probability of contraction. normal <![CDATA[Density (kg / m 3 )]]> 41 42 — — 40 39 42 40 Surface hardness (Fº) at 25°C 94 91 — — 92 62 65 85 Aperture (µm) 6054.3 4098.8 — — 4732.5 3765.4 2465.9 2890.2 Tear strength (N / mm) 1.5 1.2 — — 1.7 0.8 0.7 1.2 Tensile strength (kPa) 323.4 287.3 — — 358.1 236.5 249.7 298.6 Air permeability (l / m2 / s) 29 34 — — 26 87 75 45 Mass loss rate (%) after hydrolysis resistance test 7.6 8.7 — — 46.3 64.1 77.2 8.5

[0088] As can be seen from the physical property test data in Table 1, Examples 1, 2, 5, and 6 can prepare temperature-sensitive polyester sponges. Among them, the temperature-sensitive polyester sponge prepared in Example 1 has the best overall physical properties. Under almost the same density, its comprehensive mechanical properties (surface hardness, tear strength, and tensile strength at 25°C) are slightly better than Scrub Daddy Smiley Face cleaning sponge, and far superior to the temperature-sensitive polyester sponge prepared according to the method provided by patent CN202311294719. At the same time, the temperature-sensitive polyester sponge prepared in Example 1 has slightly lower air permeability and weight loss rate after hydrolysis resistance test than Scrub Daddy Smiley Face cleaning sponge, and far lower than the temperature-sensitive polyester sponge prepared according to the method provided by patent CN202311294719. This indicates that the temperature-sensitive polyester sponge obtained in Example 1 has a higher closed-cell rate and better hydrolysis resistance. During use, the probability of food residue and dirt residue entering the sponge and causing bacterial growth is lower, resulting in a longer service life. Furthermore, the temperature-sensitive polyester sponge obtained in Example 1 has a much larger pore size than the Scrub Daddy smiley face cleaning sponge, and its surface hardness is also higher than that of the Scrub Daddy smiley face cleaning sponge. It has greater friction when used at room temperature and is more effective at cleaning dirt.

[0089] As seen in Example 1 and Comparative Example 1, the addition of the opening agent broadened the process tolerance during the foaming of the temperature-sensitive sponge, preventing shrinkage during foaming. The effects of Examples 3 and 4 show that the amount of opening agent added significantly affects the performance of the sponge during foaming; too much leads to foam collapse, while too little leads to shrinkage, resulting in an unsuitable sponge. This result aligns with the technical concept of this patent. Comparing Example 5 with Examples 1 and 2, the absence of the long-chain diacid sebacic acid during the synthesis of the special polyester polyol resulted in a severe deterioration in the hydrolysis resistance of the final temperature-sensitive polyester sponge, increasing the mass loss rate from 7.6% to 46.3%. Comparing Example 6 with Examples 1 and 2, and with Example 5, it can be seen that the absence of long-chain diacid sebacic acid and 2,3,3',4'-biphenyltetracarboxylic dianhydride during the synthesis of the special polyester polyol not only further deteriorates the hydrolysis resistance of the temperature-sensitive polyester sponge, but also reduces the overall mechanical strength, increases the air permeability, decreases the closed-cell rate, and further reduces the overall performance of the resulting temperature-sensitive polyester sponge.

[0090] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a high hydrolysis resistant thermo-sensitive polyester sponge, characterized in that, The method comprises the following steps: obtained by reacting component A and component B, wherein the component A comprises polyester polyol, foaming agent, foaming catalyst, surfactant and cell opener; the component B comprises isocyanate or isocyanate mixture, wherein: the polyester polyol at least comprises polyester polyol a containing benzene ring, and the functionality of the polyester polyol a containing benzene ring is 2.1-2.

5.

2. The method for preparing high hydrolysis-resistant temperature-sensitive polyester sponge according to claim 1, characterized in that: the polyester polyol a containing benzene ring is obtained by reacting acid or anhydride, dihydric alcohol and synthesis catalyst under heating condition, wherein: at least one of the acid or anhydride contains benzene ring; the dihydric alcohol comprises one or a mixture of both of linear dihydric alcohol or bulk dihydric alcohol; the synthesis catalyst is one or more of stannous octoate, dibutyl tin laurate, tetrabutyl titanate or tetraisopropyl titanate, and the amount is 0.03%-0.1% of the weight of dihydric alcohol.

3. The preparation method of the high hydrolysis-resistant temperature-sensitive polyester sponge according to claim 1, wherein: the acid or anhydride is one or more of adipic acid, suberic acid, sebacic acid, phthalic anhydride, isophthalic anhydride, 2,2-bis[4-(3,4-phenoxyphenyl)]propane dianhydride or 2,3,3',4'-biphenyl tetracarboxylic dianhydride; the linear dihydric alcohol is one or more of ethylene glycol, diethylene glycol, 1,4-butanediol, 1,6-hexanediol or triethylene glycol; the bulk dihydric alcohol is one or more of neopentyl glycol, 2-methyl-1,3-propanediol, 2-methyl-2,4-pentanediol, 3-methyl-1,5-pentanediol, butyl ethyl propylene glycol or diethyl pentanediol.

4. The preparation method of the high hydrolysis-resistant temperature-sensitive polyester sponge according to claim 3, wherein: the acid or anhydride is a mixture of adipic acid, sebacic acid and 2,3,3',4'-biphenyl tetracarboxylic dianhydride, and the weight ratio of adipic acid, sebacic acid and 2,3,3',4'-biphenyl tetracarboxylic dianhydride is (50-65):(15-35):(3-10); the dihydric alcohol is a mixture of diethylene glycol and neopentyl glycol, and the weight ratio of neopentyl glycol to diethylene glycol is (3:7)-(7:3).

5. The preparation method of the high hydrolysis-resistant temperature-sensitive polyester sponge according to claim 1, wherein: the polyester polyol comprises polyester polyol a containing benzene ring and polyester polyol b; the hydroxyl value of the polyester polyol a containing benzene ring is 150-170 mgKOH / g, and the viscosity is 10000-30000 mPa·s / 25℃; the weight average molecular weight of the polyester polyol b is 2000-2500 g / mol, the functionality is 2.0, and the viscosity is 7000-20000 mPa·s / 25℃; the weight ratio of the polyester polyol a containing benzene ring to the polyester polyol b is (8:2)-(6:4).

6. The preparation method of the high hydrolysis-resistant temperature-sensitive polyester sponge according to claim 1, wherein: The foaming catalyst is one or more of tertiary amine catalysts or organometallic catalysts, and the addition amount is 0.5wt%-1wt% of the polyester polyol; The surfactant is a polyether-modified organosilicon surfactant, and the addition amount is 1wt%-2wt% of the addition amount of the polyester polyol; The addition amount of the pore-forming agent is 0.03wt%-0.3wt% of the addition amount of the polyester polyol; The foaming agent is water; The component B includes a mixture of one or more of toluene diisocyanate, diphenylmethane diisocyanate or crude MDI, and the addition amount is weighed according to the formulation index of 1.10-1.

20.

7. The method for preparing high hydrolysis-resistant temperature-sensitive polyester sponge according to claim 1, characterized in that, The preparation method of the polyester polyol a containing a benzene ring includes the following steps: adding an acid or an acid anhydride, a dihydric alcohol and a synthesis catalyst into a reaction kettle, under the protection of inert gas, stirring and mixing while heating to 105-115℃, and stirring and reacting at 105-115℃ for 1-3h; then stirring and reacting at 140-150℃, 175-185℃, 210-220℃ and 245-255℃ respectively for 1-3h to obtain the polyester polyol a containing a benzene ring.

8. The method of producing a high-hydrolysis-resistant thermo-sensitive polyester sponge according to any one of claims 1 to 7, characterized by, The preparation method includes the following steps: 1) The raw materials of component A are proportioned and stirred at a speed of 750-850RPM for 55-65s to mix uniformly; 2) Component B and component A are weighed and mixed by a blender at a speed of 1400-1600RPM for 4-6s to obtain a mixture, and then the mixture is immediately poured into a mold with built-in release film to foam to obtain a sponge body; 3) Then the obtained sponge body is left to stand and cure for 45-50h to obtain a high hydrolysis-resistant temperature-sensing polyester sponge with complete curing.

9. A high hydrolysis-resistant temperature-sensing polyester sponge prepared by the preparation method according to any one of claims 1 to 8.

10. The application of the high hydrolysis-resistant temperature-sensing polyester sponge according to claim 9, characterized in that: It is used as a hard foam at 30℃; Or, it is used as a soft foam above 50℃.