CN101130581A - Preparation method of heat-resistant amphiphilic material based on isopropenyl oxazoline polymer - Google Patents

Abstract

The invention discloses a heat-resistant amphiphilic material based on an isopropenyl oxazoline polymer and a preparation method thereof. The preparation method is to dissolve the isopropenyl oxazoline polymer and dodecanoic acid in a solvent to obtain The solution was cast on a glass slide, and after the solvent was completely evaporated at room temperature, a blend film was obtained, which was scraped off and dried in vacuum. The heat resistance of the obtained heat-resistant amphiphilic material was better than that of the surfactant. Great improvement; the method of the invention improves the heat resistance of the small molecule surfactant, expands the performance of the existing surfactant and the application range of the oxazoline polymer.

Description

Preparation method of heat-resistant amphiphilic material based on isopropenyl oxazoline polymer

technical field

The invention relates to the technical field of surfactant blending modification, in particular to a heat-resistant amphiphilic material based on isopropenyl oxazoline polymer and a preparation method thereof.

Background technique

Surfactant is a class of widely used additives and is a very important fine chemical. Surfactants have various functions and functions such as washing, wetting, emulsifying, dispersing, solubilizing, thickening, lubricating, softening, leveling, antistatic, etc. In addition to being widely used in synthetic detergent and cosmetic industries, they are also widely used Used in various fields such as textiles, printing and dyeing, papermaking, leather, petroleum, rubber, plastics, coatings, metallurgy, and metal processing. Surfactants are very important additives in the composition of coatings. As functional coatings, the application range of heat-resistant coatings is becoming wider and wider. In addition to selecting heat-resistant resins, the heat resistance of additives also has a non-negligible effect on the performance of coatings. Due to the influence of surface active agents, the heat-resistant decomposition temperature of the widely used surfactants is low, the thermal stability is poor, and they are easy to decompose and fail during thermal processing or when heated. Therefore, the commonly used surfactants are modified to improve Its heat resistance is of great significance for broadening its application fields.

U.S. Patent No. 6,465,582B1 discloses a low-molecular-weight multifunctional polyoxazoline compound as a crosslinking agent in a liquid coating composition containing a carboxyl polymer, and utilizes the oxazoline functional group to react with a carboxyl group in a co-reactant to crosslink, the invention The polyoxazoline compound can effectively achieve cross-linking and curing, but this invention does not relate to the field where the polyoxazoline compound improves the thermal stability of surfactants. At present, there is no research report on improving the heat resistance of surfactants with oxazoline polymers.

Contents of the invention

The purpose of the present invention is to combine the oxazoline polymer with the surfactant, and provide a preparation method of the heat-resistant amphiphilic material based on the isopropenyl oxazoline polymer.

The purpose of the present invention is also to provide the heat-resistant amphiphilic material based on isopropenyl oxazoline polymer prepared by the method.

A kind of preparation method of the heat-resistant amphiphilic material based on isopropenyl oxazoline polymer of the present invention is that isopropenyl oxazoline polymer and dodecanoic acid are dissolved in solvent, and the solution obtained is cast on the slide glass , after the solvent is completely evaporated at room temperature, the blend film is obtained, which is scraped off and dried in vacuum; wherein the molar ratio of the oxazoline functional group in the isopropenyl oxazoline polymer to the carboxyl functional group of dodecanoic acid is 1 : 1.

The preferred isopropenyl oxazoline polymer is a binary copolymer of isopropenyl oxazoline homopolymer or isopropenyl oxazoline monomer and a second monomer; the second monomer is styrene or ethyl acrylate, two The proportion of oxazoline monomers in the multi-polymer is more than or equal to 80% by mass.

The isopropenyl oxazoline polymer can be prepared by the following method: isopropenyl oxazoline or isopropenyl oxazoline monomer and the second monomer are dissolved in toluene, so that the total mass of the monomer accounts for the total mass of the solution 20 to 30% of the total mass of the monomers, blow nitrogen, heat to 65 ° C, add azobisisobutyronitrile with a mass of 1% of the total mass of monomers as an initiator to initiate free radical polymerization, stop polymerization after 20 to 45 hours of reaction, and use n-hexane , diethyl ether or petroleum ether as a precipitant to precipitate the polymer, filter it with suction, and dry it under vacuum at 50°C.

The solvent is preferably absolute ethanol or tetrahydrofuran.

The concentration of the mixed solution is preferably 20% by mass.

The material prepared by the method of the invention improves the heat resistance of the small molecule surfactant, expands the performance of the existing surfactant and the application range of the oxazoline polymer.

Detailed ways

Embodiment 1: Isopropenyl oxazoline homopolymer-dodecanoic acid amphiphilic material

5g isopropenyl oxazoline monomer is dissolved in the toluene of 9.6g (11ml), obtains the toluene solution of isopropenyl oxazoline; The initiator AIBN of 0.05g is dissolved in the toluene of 2g (2.3ml), obtains AIBN of toluene solution. Add the toluene solution of isopropenyloxazoline into a three-necked flask, pass nitrogen gas, and when heated to 65°C, add AIBN toluene solution, the proportion of monomers in the reaction solution to the total mass of the solution is 30%, and react at a constant temperature at 65°C for 20 hours. Cool naturally, pour into n-hexane to obtain white solid powder, filter with suction, wash with n-hexane, and vacuum-dry at 50°C to obtain isopropenyloxazoline polymer. Then the dodecanoic acid of 0.1g (0.0005mol carboxyl functional group) and the isopropenyl oxazoline polymer of 0.0555g (0.0005mol oxazoline functional group) are dissolved in the dehydrated alcohol of 0.79ml (0.623g), the concentration of solution The solution was cast on a glass slide with a syringe, and the amphiphilic material was obtained after the solvent evaporated slowly.

Embodiment 2: Amphiphilic material of isopropenyl oxazoline-styrene copolymer and dodecanoic acid

The isopropenyl oxazoline of 3.62g (0.0326mol) and the styrene monomer of 0.38g (0.0036mol) are dissolved in the toluene of 14g (16.1ml), obtain the toluene solution of isopropenyl oxazoline and styrene monomer , isopropenyloxazoline accounts for 90% of the total number of monomers; 0.04 g of AIBN is dissolved in 2 g (2.3 ml) of toluene to obtain a toluene solution of AIBN. Add the toluene solution of isopropenyloxazoline and styrene monomer to the three-necked flask, blow nitrogen, add AIBN toluene solution when heated to 65°C, the proportion of the monomer in the reaction solution to the total mass of the solution is 20%, and keep the temperature at 65°C React for 45 hours, cool naturally, pour into ether to obtain a white solid powder, filter with suction, wash with ether, and dry under vacuum at 50°C to obtain a polyisopropenyloxazoline-styrene copolymer. Then the dodecanoic acid of 0.0801g (0.0004mol) and the polyisopropenyl oxazoline-styrene copolymer of 0.0488g (0.0004mol oxazoline functional group) are dissolved in the dehydrated alcohol of 0.65ml (0.513g), solution The concentration of the solution is 20%, and the solution is cast on a glass slide with a syringe, and the amphiphilic material is obtained after the solvent evaporates slowly.

Embodiment 3: the amphiphilic material of isopropenyl oxazoline-ethyl acrylate copolymer and dodecanoic acid

The isopropenyl oxazoline of 4.08g (0.0367mol) and the ethyl acrylate monomer of 0.92g (0.0092mol) are dissolved in the toluene of 13g (15ml), obtain the toluene of isopropenyl oxazoline and ethyl acrylate monomer For the solution, the proportion of isopropenyloxazoline monomers to the total number of monomers is 80%; 0.05 g of AIBN is dissolved in 2 g (2.3 ml) of toluene to obtain a toluene solution of AIBN. Add the toluene solution of isopropenyl oxazoline and ethyl acrylate monomer into the three-necked flask, blow nitrogen, add AIBN toluene solution after heating to 65°C, the proportion of the monomer in the reaction solution to the total mass of the solution is 25%, at 65°C React at constant temperature for 30 hours, cool naturally, pour into petroleum ether to obtain white solid powder, filter with suction, wash with petroleum ether, and vacuum dry at 50°C to obtain polyisopropenyloxazoline-ethyl acrylate copolymer. Then the dodecanoic acid of 0.0801g (0.0004mol) and the polyisopropenyl oxazoline-ethyl acrylate copolymer of 0.0541g (0.0004mol oxazoline functional group) are dissolved in the THF of 0.60ml (0.5335g), the solution The concentration was 20%, and the solution was cast on a glass slide with a syringe, and the composite film was obtained after the solvent evaporated slowly.

Example 4: Dodecanoic acid and the amphiphilic material of the present invention were subjected to thermogravimetric analysis to investigate their heat resistance.

Dodecanoic acid and the amphiphilic material of the present invention are carried out thermogravimetric analysis with NETZSCH TG 209F1, to investigate the material heat resistance property prepared in embodiment 1-3, the result is as shown in table 1:

Table 1

Dodecanoic acid The material of embodiment 1 The material of embodiment 2 The material of embodiment 3  Decomposition temperature (°C) 117 132 133 120 Extrapolated onset decomposition temperature (°C) 195 230 220 245 Maximum weight loss rate temperature (°C) 218 275 276 279

It can be seen from Table 1 that the heat resistance of the amphiphilic material of the present invention is greatly improved compared with dodecanoic acid.

Claims (6)

1. a preparation method based on the heat-resistant amphiphilic material of isopropenyl oxazoline polymer, it is characterized in that, isopropenyl oxazoline polymer and dodecanoic acid are dissolved in solvent, and the solution obtained is cast in On a glass slide, after the solvent is completely evaporated at room temperature, a blend film is obtained, which is scraped off and dried in vacuum; the mole ratio of the oxazoline functional group in the isopropenyl oxazoline polymer to the carboxyl functional group of dodecanoic acid The ratio is 1:1. 2. preparation method according to claim 1, is characterized in that described isopropenyl oxazoline polymer is the binary copolymerization of isopropenyl oxazoline homopolymer or isopropenyl oxazoline monomer and the second monomer The second monomer is styrene or ethyl acrylate, and the proportion of the oxazoline monomer in the binary copolymer is more than or equal to 80% by mass. 3. The preparation method according to claim 2, wherein the isopropenyl oxazoline polymer is prepared by the following method: the isopropenyl oxazoline or isopropenyl oxazoline monomer and the second monomer Dissolve in toluene so that the total mass of the monomer accounts for 20-30% of the total mass of the solution, blow nitrogen gas, heat to 65°C, add azobisisobutyronitrile with a mass of 1% of the total mass of the monomer as an initiator to initiate free radicals Polymerization, stop the polymerization after 20-45 hours of reaction, use n-hexane, diethyl ether or petroleum ether as a precipitant to precipitate the polymer, filter it with suction, and dry it in vacuum at 50°C. 4. The preparation method according to claim 1, characterized in that the solvent is absolute ethanol or tetrahydrofuran. 5. The preparation method according to claim 4, characterized in that the concentration of the mixed solution is 20% by mass. 6. The heat-resistant amphiphilic material based on the isopropenyl oxazoline polymer prepared by the method described in one of claims 1-5.