Polyesteramide hot melt adhesive and preparation method thereof
Technical Field
The invention relates to a polyesteramide hot melt adhesive and a preparation method thereof, in particular to a low-temperature-resistant polyesteramide hot melt adhesive and a preparation method thereof, belonging to the field of adhesives.
Background
The solvent-based adhesive is the most common adhesive at present, and is easy to have adverse effects on the environment in the production and use links due to the volatility of the solvent. Meanwhile, the environmental problem becomes the first problem in the manufacturing industry, particularly the chemical industry, along with the continuous acceleration of the modernization process of our country. Among different types of bonding solutions, the hot melt adhesive has unique advantages compared with a solvent-based adhesive, so that the hot melt adhesive becomes an environment-friendly alternative of the solvent-based adhesive, and the production and application range is wider and wider.
Of the conventional hot melt adhesives, polyamide hot melt adhesives and polyester hot melt adhesives are two very important types of hot melt adhesive materials, and the adhesion effect of polyamide hot melt adhesives is generally superior to that of polyester hot melt adhesives. However, the conventional copolyamide hot melt adhesive in the current market has higher glass transition temperature (Tg is higher than 5 ℃); the conventional copolyester hot melt adhesive also generally has the problem of poor low-temperature flexibility, particularly the polyester hot melt adhesive with high melting point has high hardness, and the glass transition temperature Tg is generally < -5 ℃. When the two types of hot melt adhesives are used in a situation with lower temperature, brittle fracture is easy to occur, so that the peeling strength is greatly reduced.
Therefore, it is a problem to be solved how to provide a hot melt adhesive which combines the excellent performance of polyamide hot melt adhesives and has good low temperature resistance, and improves the applicability of related products in high-latitude cold regions.
Disclosure of Invention
The invention aims to solve the technical problems and provides a polyesteramide hot melt adhesive and a preparation method thereof, so that the polyesteramide hot melt adhesive prepared by the invention has the excellent performance of the conventional polyamide hot melt adhesive, has better low temperature resistance and meets the application requirements of specific conditions.
The technical scheme adopted by the invention is as follows: the raw materials of the polyesteramide hot melt adhesive comprise a main material and an auxiliary material, wherein the main material comprises aliphatic dicarboxylic acid, nylon 66 salt, alcohol amine and polyester polyol, and the auxiliary material comprises a catalyst and an antioxidant.
In the main material, the aliphatic dicarboxylic acid is selected from one of adipic acid, sebacic acid, dodecanedioic acid or tridecanedioic acid; the alcohol amine is selected from one of ethanolamine, n-propanolamine, isopropanolamine or n-butanolamine; the polyester polyol has a number average molecular weight of 3000, and is selected from one of polyhexamethylene glycol adipate, 1, 4-butanediol adipate, polyethylene glycol adipate and neopentyl glycol adipate.
Wherein the main material comprises the following materials in parts by weight:
aliphatic dicarboxylic acids: nylon 66 salt: the molar ratio of the sum of the alcohol amine and the polyester polyol is 1:0.3-0.7:1-1.05, and the ratio of the alcohol amine: the molar ratio of the polyester polyol is 1: 0.005-0.01.
In the auxiliary materials, the catalyst is tetrabutyl titanate, and the addition amount of the tetrabutyl titanate is 0.05-0.1 percent of the total mass of the main materials; the grade of the antioxidant is selected from one of 1010, 168 or 1096, and the addition amount of the antioxidant is 0.2-0.5 percent of the total mass of the main material.
The preparation method of the polyesteramide hot melt adhesive comprises the following steps:
(1) adding selected aliphatic dicarboxylic acid, nylon 66 salt, alcohol amine, polyester polyol, a catalyst and an antioxidant into a reaction kettle connected with a reflux device according to a preset proportion;
(2) replacing 2 times with nitrogen, slowly heating to 120 ℃, starting stirring, continuously heating to 230 ℃, and keeping the temperature between 230 ℃ and 240 ℃ for reaction for 2 hours;
(3) keeping the temperature between 230 ℃ and 240 ℃, starting vacuumizing until the pressure in the reaction kettle is 50-100Pa, and then keeping the reaction for 2 hours;
(4) introducing nitrogen to relieve vacuum, keeping the temperature of the system between 230 and 240 ℃, continuously stirring for 0.5h, and discharging to obtain the product.
The innovation of the invention is that: unique raw materials and proportions are designed, and the method is prepared by adopting the step of directly adding the raw materials for reaction. In the system, the melting point of the product can be influenced by too much adding amount of the nylon 66 salt, and the bonding effect of the product can be influenced by too little adding amount of the nylon 66 salt; too much alcohol amine can affect the glass transition temperature and the brittle temperature of the product, and too little can affect the melting point of the product; too much polyester polyol can affect the melting point and the melting index of the product, and too little can affect the glass transition temperature and the brittle temperature of the product. Compared with the conventional polyamide hot melt adhesive sold in the market with the same-grade bonding effect, the polyesteramide hot melt adhesive prepared by the invention has no difference in melting index, has lower melting point and greatly reduced glass transition temperature and embrittlement temperature, is convenient for gluing operation, and increases the adaptability of the polyesteramide hot melt adhesive in cold regions with high latitude and high altitude.
Detailed Description
The present invention will be further illustrated by the following examples, but is not limited thereto.
Example 1:
a polyesteramide hot melt adhesive comprises the following raw materials: 87.6g of adipic acid, 110.04g of nylon 66 salt, 36.23g of ethanolamine, 21g of polyhexamethylene adipate with a number average molecular weight of 3000, 0.18g of catalyst and 0.51g of antioxidant with the brand number of 1010.
The preparation method of the polyesteramide hot melt adhesive comprises the following steps:
(1) adding the aliphatic dicarboxylic acid, the nylon 66 salt, the alcohol amine, the polyester polyol, the catalyst and the antioxidant into a reaction kettle connected with a reflux device according to a preset proportion;
(2) replacing 2 times with nitrogen, slowly heating to 120 ℃, starting stirring, continuously heating to 230 ℃, and keeping the temperature between 230 ℃ and 240 ℃ for reaction for 2 hours;
(3) keeping the temperature between 230 ℃ and 240 ℃, starting vacuumizing until the pressure in the reaction kettle is 50-100Pa, and then keeping the reaction for 2 hours;
(4) introducing nitrogen to relieve vacuum, keeping the temperature of the system between 230 and 240 ℃, continuously stirring for 0.5h, and discharging to obtain the product.
A sample of the product obtained by preparation of example 1 is designated a 1.
Example 2:
a polyesteramide hot melt adhesive comprises the following raw materials: 141.4g of sebacic acid, 55.02g of nylon 66 salt, 54.86g of n-propanolamine, 12.25g of 1, 4-butanediol polyadipate having a number-average molecular weight of 3000, 0.26g of catalyst, and 1.32g of antioxidant having a brand number of 168.
The preparation method of the polyesteramide hot melt adhesive is the same as that of example 1.
A sample of the product obtained by preparation of example 2 is designated a 2.
Example 3:
a polyesteramide hot melt adhesive comprises the following raw materials: 115g of dodecanedioic acid, 91.7g of nylon 66 salt, 37.13g of isopropanolamine, 17.5g of polyethylene adipate having a number-average molecular weight of 3000, 0.13g of catalyst, and 0.52g of antioxidant having the brand number 1096.
The preparation method of the polyesteramide hot melt adhesive is the same as that of example 1.
A sample of the resulting product prepared by example 3 is labeled a 3.
Example 4:
a polyesteramide hot melt adhesive comprises the following raw materials: 146.4g of tridecanedioic acid, 47.16g of nylon 66 salt, 55.8g of n-butylamino amine, 10.5g of poly (neopentyl glycol) adipate with number-average molecular weight of 3000, 0.26g of catalyst and 1.3g of antioxidant with the brand number of 1010.
The preparation method of the polyesteramide hot melt adhesive is the same as that of example 4.
A sample of the resulting product prepared by example 4 was labeled a 4.
Example 5:
a polyesteramide hot melt adhesive comprises the following raw materials: 129.32g of tridecanedioic acid, 69.43g of nylon 66 salt, 48.21g of n-butylamino, 14 g28 g of polyhexamethylene adipate with a number-average molecular weight of 3000, 0.2g of catalyst and 0.91g of antioxidant with the brand number of 168.
The preparation method of the polyesteramide hot melt adhesive is the same as that of example 5.
A sample of the resulting product prepared by example 5 is labeled a 5.
And (3) performance testing:
the samples A1-A5 obtained in the above examples and the commercially available polyesteramide hot melt adhesive with the same grade of adhesive effect are compared by performance tests. Wherein, the peel strength test is referred to the standard GB/T11402; melting point test reference standard GB/T19466; the fused finger test reference standard GB/T3682; the vitrification quasi-temperature test is referred to GB/T19466.2; the embrittlement temperature test is referred to GB/T5470.
The results of the relevant performance tests are shown in table 1 below.
Table 1: comparison table for each sample and conventional performance tests on the market
From the above table 1, it is obvious that the polyesteramide hot melt adhesive prepared by the invention has no difference in melt index compared with the conventional polyamide hot melt adhesive with the same grade of adhesive effect, but has lower melting point and greatly reduced glass transition temperature and embrittlement temperature, is also convenient for sizing operation, and increases the adaptability of the adhesive in cold regions with high latitude and high altitude.