阅读说明：本技术 一种含2-甲基-1-丁烯-3炔提高异戊二烯橡胶聚合度的方法 (Method for improving polymerization degree of isoprene rubber by using 2-methyl-1-butene-3 alkyne ) 是由 王元瑞 高东旭 于 2019-11-21 设计创作，主要内容包括：本发明涉及2-甲基-1-丁烯-3-炔异戊二烯橡胶的制备方法。该方法是以配制不同浓度范围为0.001%—0.01%的2-甲基-1-丁烯-3炔的己烷溶液,通过气相色谱准确定量,将已配制好的不同浓度2-甲基-1-丁烯-3-炔掺入异戊二烯中,加入以稀土烷基铝混合催化剂进行聚合反应,干燥称量测其质量以评价杂质浓度变化对橡胶聚合影响的情况。该材料作为人工合成橡胶,面对天然橡胶供应紧张的局面,寻求其作为替代品,人工合成橡胶也是解决天然橡胶供应问题的有效途径之一。(The invention relates to a preparation method of 2-methyl-1-butene-3-alkyne isoprene rubber. The method comprises the steps of preparing hexane solutions of 2-methyl-1-butene-3 alkyne with different concentration ranges of 0.001% -0.01%, accurately quantifying through gas chromatography, doping the prepared 2-methyl-1-butene-3-alkyne with different concentrations into isoprene, adding a rare earth alkyl aluminum mixed catalyst for polymerization reaction, and measuring the quality of the mixture by a drying scale to evaluate the influence of impurity concentration change on rubber polymerization. The material is used as artificial synthetic rubber, and is sought to be used as a substitute in the situation of shortage of natural rubber supply, and the artificial synthetic rubber is also one of effective ways for solving the problem of natural rubber supply.)

A method for preparing 2-methyl-1-butene-3-alkynisoprene rubber, which is characterized by comprising the following steps:

(1) preparing a hexane solution of 2-methyl-1-butene-3 alkyne with a certain concentration, and accurately quantifying by gas chromatography;

(2) diluting the prepared hexane mother liquor of the 2-methyl-1-butene-3 alkyne into different concentrations by using hexane, and accurately quantifying by using a gas chromatography;

(3) doping prepared 2-methyl-1-butene-3-alkyne impurities with different concentrations into isoprene, adding a rare earth alkyl aluminum mixed catalyst, and carrying out polymerization reaction in a thermostatic water bath;

(4) the rubber was blown dry and the conversion was measured to evaluate the effect of the change in impurity concentration on the polymerization of the rubber.

2. The process for producing a 2-methyl-1-butene-3-yne isoprene rubber according to claim 1, wherein in the step (1), the content of 2-methyl-1-butene-3-yne is 0.1100g, the mass of hexane is 66.0457g, and the concentration of 2-methyl-1-butene-3-yne in the mother liquor is 0.167% g/ml in terms of theoretical calculation.

3. The process for producing a 2-methyl-1-butene-3-alkynisoprene rubber according to claim 1, wherein the concentration of 2-methyl-1-butene-3 alkynes in the mother liquor in step (1) is measured by gas chromatography to be 0.193% g/ml.

4. The method for producing 2-methyl-1-butene-3-alkynisoprene rubber according to claim 1, wherein the mass of hexane in the step (1) is 66.0457g, and the hexane solution is 42.5 ml.

5. The method for preparing 2-methyl-1-butene-3-alkynisoprene rubber according to claim 1, wherein the rare earth alkylaluminum mixed catalyst in step (3) is a mixture of neodymium neodecanoate, 1-nitrogen-2-isobutylaluminum and triethylaluminum, and the concentration thereof is 3 x 10^-6g/mol。

6. The process for producing 2-methyl-1-butene-3-yne isoprene rubber according to claim 1, wherein the volume of isoprene in the step (3) is 7.5ml, and the density is 0.681g/cm³。

7. The method for preparing 2-methyl-1-butene-3-alkynisoprene rubber according to claim 2, wherein the heating temperature of the thermostatic waterbath in the step (3) is 50 ℃ and the temperature is maintained for 3 hours.

8. The method for preparing 2-methyl-1-butene-3-alkynisoprene rubber according to claim 1, wherein the drying temperature in step (4) is 50 ℃ and the blowing-drying is carried out for 24 hours.

Technical Field

The invention relates to the field of material chemistry, in particular to a preparation method of 2-methyl-1-butene-3-alkyne isoprene rubber.

Background

Polyisoprene rubber is cis-1, 4-polyisoprene rubber, which is abbreviated as isoprene rubber, also called synthetic natural rubber, is the third major rubber species of the world synthetic rubber which is only inferior to styrene-butadiene rubber and butadiene rubber, and has attracted great interest of various academicians since the advent. It can be seen from the comparison of the properties of various synthetic rubbers with those of natural rubbers: isoprene rubber has many properties similar to natural rubber, such as excellent elasticity, abrasion resistance, heat resistance, low-temperature flexibility, and the like, and the heat resistance thereof exceeds even natural rubber. How to improve the current situation of 'no-rice cooking' of natural rubber, an important raw material in the rubber industry, becomes a problem of general attention in the industry.

2-methyl-1-buten-3-yne as C₅One of the impurities of isoprene in the cleavage fraction. The content of the impurity concentration thereof more or less directly affects the degree of polymerization of the isoprene rubber. From C₅The extraction and separation of isoprene from the components has the lowest production cost and is more competitive. By cracking C₅The isoprene resource in the components is used for producing isoprene rubber, so that the condition that the natural rubber in China has high dependence on the outside at present can be relieved, and the method is an important measure for improving the comprehensive utilization rate of ethylene industrial resources.

The rare earth alkyl aluminum mixed catalyst is a mixture of neodymium neodecanoate, 1-nitrogen-2-isobutyl aluminum and triethyl aluminum. Can improve the content of the crude rubber cis-1, 4-isoprene rubber and avoid generating insoluble substances. Large average relative molecular mass of raw rubber, narrow distribution, short vulcanization processing time and small catalyst consumption.

Disclosure of Invention

The invention provides a preparation method of 2-methyl-1-butene-3-alkyne, aiming at overcoming the technical defects.

The method comprises the steps of preparing hexane solutions of 2-methyl-1-butene-3 alkyne with different concentration ranges of 0.001% -0.01%, accurately quantifying through gas chromatography, doping the prepared 2-methyl-1-butene-3-alkyne with different concentrations into isoprene, adding a rare earth alkyl aluminum mixed catalyst for polymerization reaction, and measuring the quality of the mixture by a drying scale to evaluate the influence of concentration change on rubber polymerization.

The method specifically comprises the following steps:

(1) preparing hexane solution of 2-methyl-1-butene-3 alkyne with different concentration ranges of 0.001% -0.01%, and accurately quantifying by gas chromatography;

(2) diluting the prepared hexane mother liquor of the 2-methyl-1-butene-3 alkyne into different concentrations by using hexane, and accurately quantifying by using a gas chromatography;

(3) doping prepared 2-methyl-1-butene-3-alkyne with different concentrations into isoprene, adding a rare earth alkyl aluminum mixed catalyst, and carrying out polymerization reaction in a thermostatic water bath;

(4) blowing and drying, weighing and calculating the conversion rate to evaluate the influence of concentration change on rubber polymerization;

in the step (1), the content of the 2-methyl-1-butene-3-alkyne is 11.7042g, and the concentration of the 2-methyl-1-butene-3-alkyne in the mother liquor is 0.167 percent g/ml and the purity is 98 percent by theoretical calculation.

The concentration of 2-methyl-1-butene-3 alkyne in the mother liquor in the step (1) was measured by gas chromatography to be 0.193% g/ml.

The mass of the hexane in the step (1) is 66.0457g, and the volume of the hexane solution is 42.5 ml.

The rare earth alkyl aluminum mixed catalyst in the step (3) is a mixture of neodymium neodecanoate, 1-nitrogen-2-isobutyl aluminum and triethyl aluminum, and the concentration of the mixture is 3 multiplied by 10^-6g/mol。

In the step (3), the volume of the isoprene is 7.5ml, and the density is 0.681g/cm³。

And (4) heating the mixture in the step (3) in a constant-temperature water bath at 50 ℃ for 3 hours.

And (4) blowing and drying for 24 hours at the drying temperature of 50 ℃.

Compared with the existing natural rubber, the preparation method of the 2-methyl-1-butene-3-alkyne isoprene rubber has the advantages that the isoprene rubber is used as a universal synthetic rubber, the structure and the performance of the isoprene rubber are basically the same as those of the natural rubber, and the rare earth alkyl aluminum catalyst synthetic rubber has the advantages of low catalyst dosage, large relative molecular mass of a polymer and the like compared with the conventional titanium catalyst used internationally, so that the synthetic rubber becomes a research hotspot and has wider application prospect.

Drawings

FIG. 1 is a graph showing the relative molecular weight distribution of 2-methyl-1-butene-3-alkynylisoprene prepared in example 1;

FIG. 2 is a graph showing the relative molecular weight distribution of 2-methyl-1-butene-3-alkynylisoprene prepared in example 2;

FIG. 3 is a graph showing the relative molecular weight distribution of 2-methyl-1-butene-3-alkynylisoprene prepared in example 3.

Detailed Description

The invention will be further illustrated with reference to the following specific examples.