Preparation method of liquid aliphatic resin

文档序号:388692 发布日期:2021-12-14 浏览:40次 中文

阅读说明:本技术 一种液态脂肪族树脂的制备方法 (Preparation method of liquid aliphatic resin ) 是由 杨孟君 王斌 孙向东 于 2021-09-03 设计创作,主要内容包括:本发明涉及一种液态脂肪族树脂的制备方法,包括将顺式1,3-戊二烯和环戊烯富集C5馏分与异戊二烯混合作为聚合原料,经气体三氟化硼催化获得聚合液A,经进一步处理后得到低聚物。该低聚物与改性组分混合,加压热聚得到聚合液B,闪蒸脱除轻组分即得到液态脂肪族树脂。本发明工艺简便,制备的液态树脂具有较好的相容性能和环保性能,可应用于环氧树脂、聚氨酯、聚硫橡胶等领域的改性。(The invention relates to a preparation method of liquid aliphatic resin, which comprises the steps of mixing cis-1, 3-pentadiene and cyclopentene enriched C5 fractions with isoprene as polymerization raw materials, obtaining polymerization liquid A through catalysis of gaseous boron trifluoride, and further processing to obtain an oligomer. The oligomer and the modified component are mixed, pressurized and thermally polymerized to obtain a polymerization liquid B, and the light component is removed by flash evaporation to obtain the liquid aliphatic resin. The invention has simple and convenient process, and the prepared liquid resin has better compatibility and environmental protection performance and can be applied to the modification in the fields of epoxy resin, polyurethane, polysulfide rubber and the like.)

1. A method of preparing a liquid aliphatic resin, comprising:

(1) uniformly mixing the cis-1, 3-pentadiene and the cyclopentene-enriched C5 fraction with isoprene according to the mass ratio of 1 (0-0.2) to obtain a polymerization raw material; adding a solvent accounting for 10-30% of the total mass of the materials into a high-pressure reaction kettle A with stirring in advance, cooling to-10-15 ℃, and filling N2Protection is carried out; respectively and continuously adding the polymerization raw materials and gaseous boron trifluoride accounting for 0.1-0.5% of the total mass of the materials, and after feeding is finished, heating to 20-30 ℃ to continue reacting for 0.5-1 h to obtain a polymerization solution A;

(2) mixing the polymerization solution A with a sodium hydroxide solution, adding a surfactant, carrying out alkaline washing at 50-75 ℃ to remove a boron trifluoride catalyst, carrying out electric desalting, and then removing a solvent and unreacted materials in a rectifying tower at a vacuum degree of-0.08-0.09 MPa and a temperature of 200-280 ℃ to obtain an oligomer;

(3) passing the oligomer through an active alumina bed to remove impurities and trace water, conveying the oligomer into a high-pressure reaction kettle B with stirring, and introducing N into the kettle2Protecting and pressurizing to 0.5-2.0 MPa, simultaneously adding a modification component accounting for 0.1-15.0% of the mass of the oligomer, and reacting at 180-260 ℃ for 0.5-3 h to obtain a polymerization solution B;

(4) and (3) conveying the polymerization liquid B to a flash tank, and removing light components by flash evaporation at the vacuum degree of-0.08 to-0.09 MPa and the temperature of 150 to 280 ℃ to obtain the liquid aliphatic resin.

2. The method of claim 1, wherein: the composition of the cis-1, 3-pentadiene and cyclopentene-enriched C5 fraction in the step (1) is as follows: 35-50% of cis-1, 3-pentadiene, 30-40% of cyclopentene, 0-4.0% of trans-1, 3-pentadiene, 0-2.0% of isoprene, 0-2.0% of 2-methyl-2-butene, 10-20% of cyclopentane and the balance of saturated components of C5-C6.

3. The method of claim 1, wherein: the solvent in the step (1) is one or more of cyclopentane, methylcyclopentane, cyclohexane and methylcyclohexane.

4. The method of claim 1, wherein: the feeding time in the step (1) is 0.5-2 h.

5. The method of claim 1, wherein: the mass concentration of the sodium hydroxide solution in the step (2) is 15%.

6. The method of claim 1, wherein: the surfactant in the step (2) is alkylphenol polyoxyethylene APEO or polyoxyethylene amine, and the addition amount of the surfactant is 0.05-0.3% of the mass of the polymerization liquid A.

7. The method of claim 1, wherein: the operation conditions of the electric desalting device in the step (2) are that the pressure is 0.15-0.35 MPa and the temperature is 60-80 ℃.

8. The method of claim 1, wherein: the specification of the activated alumina in the step (3) is that the particle size is 3-5 mm, and the pore volume is 0.35-0.60 cm3(ii) a BET specific surface area of 280 to 320m2/g。

9. The method of claim 1, wherein: the modified component in the step (3) is one or more of 2-methyl-1-butene, 2-methyl-2-butene, 3-methyl-1-butene, 2-dimethyl-1-butene, 1, 3-cyclohexadiene, 5-vinyl-2-norbornene, maleic anhydride, phenol and p-tert-butylphenol.

10. The method of claim 1, wherein: the softening point of the liquid aliphatic resin obtained in the step (4) is-20 ℃, the melt viscosity is 50-800 mPa & s, and the weight average molecular weight is 500-1400.

Technical Field

The invention belongs to the field of epoxy resin, and particularly relates to a preparation method of liquid aliphatic resin.

Background

Epoxy resin coating is a kind of coating using epoxy resin as main film forming substance, and its kinds are numerous, and each has its characteristics, and can be extensively used in the fields of building, chemical industry, automobile, ship and ship, electric insulation and others. The epoxy resin contains hydroxyl, ether bond and epoxy group with great activity in the structure, and has high bonding strength with various metals and most non-metal materials, good processing performance, small shrinkage, good medium resistance and good electric insulation performance. However, it is generally brittle and has poor impact resistance, and it loses gloss and powdering after being exposed to the sun outdoors, and its aging resistance is insufficient, so it is usually necessary to add an additional auxiliary agent to improve its flexibility, stability, weatherability, etc.

Solid aromatic resin, coumarone resin and the like are the most commonly used epoxy coating modifiers, and can improve the surface construction adaptability of the coating. However, the solid resin is not easily dispersed uniformly in the epoxy resin coating material due to its high softening point, and causes defects such as bubbles, wrinkles, scorching on the surface of the coating film, so that the use of the liquid resin as a modifier has a very significant advantage. Meanwhile, with the requirement for environmental protection of products being improved, the application range of the traditional aromatic liquid resin is greatly limited, so that the development of a safe and environment-friendly liquid resin with excellent compatibility with epoxy resin is required.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a preparation method of liquid aliphatic resin, the liquid aliphatic resin with lower softening point and normal-temperature melt viscosity is obtained by the method, the liquid aliphatic resin has proper molecular weight distribution and better compatibility, and can be applied to the fields of epoxy resin coating modification and the like.

The invention provides a preparation method of liquid aliphatic resin, which comprises the following steps:

(1) uniformly mixing the cis-1, 3-pentadiene and the cyclopentene-enriched C5 fraction with isoprene according to the mass ratio of 1 (0-0.2) to obtain a polymerization raw material; adding a solvent accounting for 10-30% of the total mass of the materials into a high-pressure reaction kettle A with stirring in advance, cooling to-10-15 ℃, and filling N2To carry out protection(ii) a Respectively and continuously adding the polymerization raw materials and gaseous boron trifluoride accounting for 0.1-0.5% of the total mass of the materials, and after feeding is finished, heating to 20-30 ℃ to continue reacting for 0.5-1 h to obtain a polymerization solution A;

(2) mixing the polymerization solution A with a sodium hydroxide solution, adding a surfactant, carrying out alkaline washing at 50-75 ℃ to remove a boron trifluoride catalyst, carrying out electric desalting, and then removing a solvent and unreacted materials in a rectifying tower at a vacuum degree of-0.08-0.09 MPa and a temperature of 200-280 ℃ to obtain an oligomer;

(3) passing the oligomer through an active alumina bed to remove impurities and trace water, conveying the oligomer into a high-pressure reaction kettle B with stirring, and introducing N into the kettle2Protecting and pressurizing to 0.5-2.0 MPa, simultaneously adding a modification component accounting for 0.1-15.0% of the mass of the oligomer, and reacting at 180-260 ℃ for 0.5-3 h to obtain a polymerization solution B;

(4) and (3) conveying the polymerization liquid B to a flash tank, and removing light components by flash evaporation at the vacuum degree of-0.08 to-0.09 MPa and the temperature of 150 to 280 ℃ to obtain the liquid aliphatic resin.

The composition of the cis-1, 3-pentadiene and cyclopentene-enriched C5 fraction in the step (1) is as follows: 35-50% of cis-1, 3-pentadiene, 30-40% of cyclopentene, 0-4.0% of trans-1, 3-pentadiene, 0-2.0% of isoprene, 0-2.0% of 2-methyl-2-butene, 10-20% of cyclopentane and the balance of saturated components of C5-C6. The reason why the cis-1, 3-pentadiene and the cyclopentene-enriched C5 fraction are selected as polymerization raw materials is that cis-1, 3-pentadiene is weak in activity and a low-molecular-weight liquid resin can be obtained more easily under the catalysis of BF 3.

The solvent in the step (1) is one or more of cyclopentane, methylcyclopentane, cyclohexane and methylcyclohexane.

The total mass of the materials in the step (1) refers to the sum of the mass of the cis-1, 3-pentadiene and cyclopentene enriched C5 fraction, isoprene, solvent and gaseous boron trifluoride.

The feeding time in the step (1) is 0.5-2 h.

The mass concentration of the sodium hydroxide solution in the step (2) is 15%.

The surfactant in the step (2) is alkylphenol polyoxyethylene APEO or polyoxyethylene amine, and the addition amount of the surfactant is 0.05-0.3% of the mass of the polymerization liquid A. The surfactant is used for enhancing the alkali washing effect and is beneficial to the subsequent electric desalting process.

The operation conditions of the electric desalting device in the step (2) are that the pressure is 0.15-0.35 MPa and the temperature is 60-80 ℃.

The specification of the activated alumina in the step (3) is that the particle size is 3-5 mm, and the pore volume is 0.35-0.60 cm3(ii) a BET specific surface area of 280 to 320m2/g。

The modified component in the step (3) is one or more of 2-methyl-1-butene, 2-methyl-2-butene, 3-methyl-1-butene, 2-dimethyl-1-butene, 1, 3-cyclohexadiene, 5-vinyl-2-norbornene, maleic anhydride, phenol and p-tert-butylphenol.

The liquid aliphatic resin obtained in the step (4) has a softening point of-20 ℃, a melt viscosity (25 ℃) of 50-800 mPa · s, and a weight average molecular weight of 500-1400.

Advantageous effects

(1) The invention has simple and convenient process, and the prepared liquid aliphatic resin has the characteristics of no aromatic group, low halogen content, low organic matter volatile matter content and better environmental protection performance.

(2) According to the invention, the softening point and the molecular weight of the liquid aliphatic resin are adjusted to enable the liquid aliphatic resin to have proper normal-temperature melt viscosity and glass transition temperature (Tg), so that the compatibility with materials such as epoxy resin, polyurethane, polysulfide rubber and the like can be improved, and the liquid aliphatic resin can be applied to toughening and rigidity-increasing modification of a coating.

(3) When the modified component contains a polar group (such as phenol and p-tert-butylphenol) in the preparation process, the modified liquid aliphatic resin with the hydroxyl value of 50-500 mgKOH/g can be obtained.

Drawings

FIG. 1 is a schematic process flow diagram of the present invention.

Detailed Description

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

Typical compositions of the cis-1, 3-pentadiene and cyclopentene-rich C5 fractions used in the examples are shown in Table 1 below:

TABLE 1 typical composition of C5 fraction

Components Content, wt%
Cis-1, 3-pentadiene 43.6
Trans-1, 3-pentadiene 2.3
Isoprene (I) 1.5
2-methyl-2-butene 1.1
Cyclopentene 33.4
Cyclopentane 14.2
The rest saturated components of C5-C6 3.9

Example 1

Uniformly mixing the C5 fraction and isoprene according to the mass ratio of 1: 0.1 to obtain a polymerization raw material, wherein the polymerization raw material comprises the following components: 40.9 percent of cis-1, 3-pentadiene, 30.0 percent of cyclopentene, 1.8 percent of trans-1, 3-pentadiene, 10.4 percent of isoprene, 1.0 percent of 2-methyl-2-butene, 12.5 percent of cyclopentane and the balance of saturated components of C5-C6.

Adding cyclopentane accounting for 25% of the total material mass in a high-pressure reaction kettle A with stirring in advance, cooling to 0 ℃, and charging N2Protection is carried out; then continuously adding the polymerization raw materials and gas boron trifluoride accounting for 0.1 percent of the total mass of the materials respectively, and feeding for 0.75 h; after the feeding is finished, heating to 20 ℃ and continuing the reaction for 1h to obtain a polymerization solution A.

Mixing the polymerization solution A with 15% of sodium hydroxide solution, adding 0.3% of alkylphenol polyoxyethylene, carrying out alkali washing at 75 ℃ to remove boron trifluoride catalyst, feeding into an electric desalting device for coalescence separation to remove water and impurity salt, wherein the operation condition is 0.15MPa, and the temperature is 65 ℃. Then removing the solvent and unreacted materials in a rectifying tower at the vacuum degree of-0.085 MPa and the temperature of 240 ℃ to obtain the oligomer.

The oligomer is passed through an active alumina bed to remove impurities and trace water and sent to a high-pressure reaction kettle B with a stirrer. Introducing N into the kettle2Protecting and pressurizing to 1.0MPa, simultaneously adding a modified component 2-methyl-1-butene accounting for 3.5 percent of the mass of the oligomer, reacting for 1.5 hours at 245 ℃ to obtain a polymerization liquid B, and then removing light components in a flash tank with the vacuum degree of-0.085 MPa at the temperature of 205 ℃ to obtain the liquid aliphatic resin with the softening point of 6.7 ℃, the melt viscosity of 122 mPa.s, the Mw of 788 and the glass transition temperature (Tg) of-33 ℃.

Examples 2 to 4

Examples 2 to 5 the liquid petroleum resin obtained by adjusting the content of isoprene in the polymerization raw material under the same conditions as in example 1 had the following properties:

the polymerization raw materials of example 2 comprise: 43.8 percent of cis-1, 3-pentadiene, 30.0 percent of cyclopentene, 2.0 percent of trans-1, 3-pentadiene, 1.5 percent of isoprene, 1.1 percent of 2-methyl-2-butene, 14.2 percent of cyclopentane and the balance of saturated components of C5-C6.

The polymerization feed composition of example 3 was: 40.6 percent of cis-1, 3-pentadiene, 30.6 percent of cyclopentene, 1.9 percent of trans-1, 3-pentadiene, 8.8 percent of isoprene, 1.0 percent of 2-methyl-2-butene, 13.2 percent of cyclopentane and the balance of saturated components of C5-C6.

The polymerization feed composition of example 4 was: 38.1 percent of cis-1, 3-pentadiene, 28.7 percent of cyclopentene, 1.7 percent of trans-1, 3-pentadiene, 14.4 percent of isoprene, 1.0 percent of 2-methyl-2-butene, 12.4 percent of cyclopentane and the balance of saturated components of C5-C6.

From examples 2 to 4, it is known that the softening point, the weight average molecular weight and the melt viscosity of the resin are gradually reduced and the glass transition temperature (Tg) is changed within a certain range with the increase of the content of isoprene in the polymerization raw material, which is helpful for being used as a plasticizing component in different liquid epoxy resin formulations.

Example 5

The polymerization raw materials of this example were the same as those of example 1. Adding a solvent accounting for 25 percent of the total material mass into a high-pressure reaction kettle A with stirring in advance, cooling to 0 ℃, and filling N2Protection is carried out; then continuously adding the polymerization raw materials and gas boron trifluoride accounting for 0.1 percent of the total mass of the materials respectively, and feeding for 0.75 h; after the feeding is finished, heating to 20 ℃ and continuing the reaction for 1h to obtain a polymerization solution A.

Mixing the polymerization solution A with 15% of sodium hydroxide solution, adding 0.3% of surfactant alkylphenol polyoxyethylene ether, carrying out alkali washing at 75 ℃ to remove boron trifluoride catalyst, feeding into an electric desalting device for coalescence and separation to remove water and impurity salts, wherein the operating condition is 0.15MPa and the temperature is 65 ℃. Then removing the solvent and unreacted materials in a rectifying tower at the vacuum degree of-0.085 MPa and the temperature of 240 ℃ to obtain the oligomer.

Removing impurities and trace water from the oligomer by an activated alumina bed, and conveying toAnd (3) a high-pressure reaction kettle B with stirring. Introducing N into the kettle2Protecting and pressurizing to 1.0MPa, simultaneously adding a modification component 5-vinyl-2 norbornene accounting for 10% of the mass of the oligomer, reacting for 2.0h at 240 ℃ to obtain a polymerization liquid B, and then removing light components in a flash tank with the vacuum degree of-0.085 MPa at the temperature of 205 ℃ to obtain the liquid aliphatic petroleum resin with the softening point of-18.5 ℃, the melt viscosity of 50 mPa.s, the Mw of 522 and the glass transition temperature (Tg) of very low-55 ℃.

Example 6

This example used the same polymerization starting materials as in example 1. Adding cyclopentane accounting for 25% of the total material mass in a high-pressure reaction kettle A with stirring in advance, cooling to 10 ℃, and filling N2Protection is carried out; then continuously adding the polymerization raw materials and gas boron trifluoride accounting for 0.2 percent of the total mass of the materials respectively, and feeding for 0.75 h; after the feeding is finished, heating to 20 ℃ and continuing the reaction for 1h to obtain a polymerization solution A. Mixing the polymerization solution A with 15% of sodium hydroxide solution, adding 0.1% of surfactant polyoxyethylene amine, carrying out alkali washing at 75 ℃ to remove a catalyst, and carrying out coalescence separation in an electric desalting device to remove water and impurity salts, wherein the operation condition is 0.30MPa, and the temperature is 80 ℃. Then removing the solvent and unreacted materials in a rectifying tower at the vacuum degree of-0.085 MPa and the temperature of 240 ℃ to obtain the oligomer.

The oligomer is removed with impurities and trace water through an active alumina bed and is conveyed into a high-pressure reaction kettle B with a stirrer. Introducing N into the kettle2Protecting and pressurizing to 1.0MPa, simultaneously adding a modified component 1, 3-cyclohexadiene accounting for 5 percent of the mass of the oligomer, reacting for 2.0h at 250 ℃ to obtain a polymerization liquid B, and then removing light components in a flash tank with the vacuum degree of-0.09 MPa at the temperature of 250 ℃ to obtain the liquid aliphatic petroleum resin with the softening point of 10.5 ℃, the melt viscosity of 150mPa & s, the Mw of 820, the glass transition temperature (Tg) of-28 ℃, the content of organic volatile matters of less than 0.1 percent and the halogen of less than or equal to 10 ppm. The modified epoxy resin has good compatibility and excellent environmental protection performance, and is suitable for modification of high-grade environmental protection coatings.

Example 7

Uniformly mixing the C5 fraction and isoprene according to the mass ratio of 1: 0.2 to obtain a polymerization raw material, wherein the composition of the polymerization raw material is as follows: 40.9 percent of cis-1, 3-pentadiene, 30.0 percent of cyclopentene, 1.8 percent of trans-1, 3-pentadiene, 10.4 percent of isoprene, 1.0 percent of 2-methyl-2-butene, 12.5 percent of cyclopentane and the balance of saturated components of C5-C6.

Adding cyclopentane accounting for 25% of the total material mass in a high-pressure reaction kettle A with stirring in advance, cooling to 0 ℃, and charging N2Protection is carried out; then continuously adding the polymerization raw materials and gas boron trifluoride accounting for 0.1 percent of the total mass of the materials respectively, and feeding for 0.75 h; after the feeding is finished, heating to 20 ℃ and continuing the reaction for 1h to obtain a polymerization solution A. Mixing the polymerization solution A with 15% of sodium hydroxide solution, adding 0.1% of surfactant polyoxyethylene amine, carrying out alkali washing at 75 ℃ to remove a catalyst, and carrying out coalescence separation in an electric desalting device to remove water and impurity salts, wherein the operation condition is 0.30MPa, and the temperature is 80 ℃. Then removing the solvent and unreacted materials in a rectifying tower at the vacuum degree of-0.085 MPa and the temperature of 240 ℃ to obtain the oligomer.

The oligomer is removed with impurities and trace water through an active alumina bed and is conveyed into a high-pressure reaction kettle B with a stirrer. Introducing N into the kettle2Protecting and pressurizing to 1.0MPa, simultaneously adding a modification component MAH accounting for 3.0 percent of the mass of the oligomer, reacting for 2.0h at 240 ℃ to obtain a polymerization solution B, and then removing light components in a flash tank with the vacuum degree of-0.085 MPa at the temperature of 205 ℃ to obtain the liquid aliphatic petroleum resin with the softening point of-18.5 ℃, the melt viscosity of 50mPa & s, the Mw of 522 and the glass transition temperature (Tg) of very low-55 ℃.

Example 8

This example used the same polymerization starting materials as in example 1. Adding cyclopentane accounting for 25% of the total material mass in a high-pressure reaction kettle A with stirring in advance, cooling to 0 ℃, and charging N2Protection is carried out; then continuously adding the polymerization raw materials and gas boron trifluoride accounting for 0.2 percent of the total mass of the materials respectively, and feeding for 0.75 h; after the feeding is finished, heating to 15 ℃ and continuing the reaction for 1h to obtain a polymerization solution A. Mixing the polymerization solution A with 15% sodium hydroxide solution, adding 0.05% of surfactant APEO, washing with alkali at 75 deg.C to remove catalyst, feeding into an electric desalting device for coalescence separation to remove water and impurity salt, and operatingThe conditions are 0.35MPa and the temperature is 65 ℃. Then removing the solvent and unreacted materials in a rectifying tower at the vacuum degree of-0.085 MPa and the temperature of 240 ℃ to obtain the oligomer.

The oligomer is removed with impurities and trace water through an active alumina bed and is conveyed into a high-pressure reaction kettle B with a stirrer. Introducing N into the kettle2Protecting and pressurizing to 1.0MPa, simultaneously adding a modified component p-tert-butylphenol (PTBP) accounting for 2.5 percent of the mass of the oligomer, reacting for 1.0h at 190 ℃ to obtain a polymer liquid B, and then removing light components in a flash tank with the vacuum degree of-0.09 MPa at 230 ℃ to obtain the liquid aliphatic petroleum resin with the softening point of 12 ℃, the melt viscosity of 86 mPa.s, the Mw of 574 and the hydroxyl value of 66mgKOH/g, which can be applied to heavy anti-corrosive epoxy coating.

Example 9

This example used the same polymerization starting materials as in example 7. Adding methylcyclohexane accounting for 25% of the total mass of the materials into a high-pressure reaction kettle A with stirring in advance, cooling to 0 ℃, and filling N2Protection is carried out; then continuously adding the polymerization raw materials and gas boron trifluoride accounting for 0.1 percent of the total mass of the materials respectively, and feeding for 0.75 h; after the feeding is finished, heating to 20 ℃ and continuing the reaction for 1h to obtain a polymerization solution A. Mixing the polymerization solution A with 15% of sodium hydroxide solution, adding 0.1% of surfactant polyoxyethylene amine, carrying out alkali washing at 75 ℃ to remove a catalyst, and carrying out coalescence separation in an electric desalting device to remove water and impurity salts, wherein the operation condition is 0.30MPa, and the temperature is 80 ℃. Then removing the solvent and unreacted materials in a rectifying tower at the vacuum degree of-0.085 MPa and the temperature of 240 ℃ to obtain the oligomer.

The oligomer is removed with impurities and trace water through an active alumina bed and is conveyed into a high-pressure reaction kettle B with a stirrer. Introducing N into the kettle2Protecting and pressurizing to 1.0MPa, simultaneously adding a modified component phenol accounting for 2.5 percent of the mass of the oligomer, reacting for 1.0h at 210 ℃ to obtain a polymer liquid B, and then removing light components in a flash tank with the vacuum degree of-0.09 MPa and the temperature of 230 ℃ to obtain the liquid aliphatic petroleum resin with the softening point of 10.5 ℃, the melt viscosity of 78mPa & s, the Mw of 550 and the hydroxyl value of 74mgKOH/g, which can be applied to heavy anti-corrosion epoxy coating.

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