Copolymerization high-temperature-resistant nylon and preparation method and application thereof
阅读说明：本技术 一种共聚耐高温尼龙及其制备方法和用途 (Copolymerization high-temperature-resistant nylon and preparation method and application thereof ) 是由 刘浩宇 高敬民 邓慧 于 2019-08-23 设计创作，主要内容包括：本发明提供一种共聚耐高温尼龙及其制备方法和用途,所述共聚耐高温尼龙为包含下述通式(Ⅰ)所示的重复结构单元、下述通式(Ⅱ)所示的重复结构单元和下述通式(Ⅲ)所示的重复结构单元的尼龙树脂。本申请中结构的耐高温尼龙光稳定性能更加突出,能在根本上改善耐高温尼龙易黄变的问题,具有很好的染色性能,具有较高的玻璃化转变温度、较高的成炭率和优异的阻燃性能。(The invention provides a copolymerized high-temperature-resistant nylon and a preparation method and application thereof, wherein the copolymerized high-temperature-resistant nylon is nylon resin containing a repeating structural unit shown in a general formula (I), a repeating structural unit shown in a general formula (II) and a repeating structural unit shown in a general formula (III). The high-temperature-resistant nylon with the structure has more outstanding light stability, can fundamentally improve the problem that the high-temperature-resistant nylon is easy to yellow, has good dyeing property, and has higher glass transition temperature, higher char yield and excellent flame retardant property.)
1. The copolymerized high-temperature-resistant nylon is characterized by being nylon resin containing a repeating structural unit shown in a general formula (I), a repeating structural unit shown in a general formula (II) and a repeating structural unit shown in a general formula (III);
wherein a, b, c and d are all positive integers more than or equal to 4;
the structure of X is general formula (IV):
wherein R is selected from the following functional groups:
2. the copolymerized high temperature resistant nylon of claim 1, comprising one or more of the following characteristics:
a is 6, 9, 10 or 12;
b is 6, 9, 10 or 12;
c is 4, 8 or 10;
d is 6, 9 and 10.
3. The copolymerized high-temperature-resistant nylon of claim 1, wherein the mass fraction of the repeating structural unit represented by the general formula (I) is 60 to 75%, the mass fraction of the repeating structural unit represented by the general formula (II) is 5 to 15%, and the mass fraction of the repeating structural unit represented by the general formula (III) is 10 to 35%, based on the total mass of the repeating units.
4. A method for preparing the copolymerized high temperature nylon of any one of claims 1 to 3, comprising the steps of:
reacting dibasic acid with X structural characteristics with aliphatic diamine to form salt to obtain a component A;
then adding semi-aromatic nylon salt, full aliphatic nylon salt, water and a capping agent for copolymerization to obtain the product.
5. The method according to claim 4, wherein the dibasic acid having the structural feature of X is one or more selected from the following structures:
wherein R is selected from the following functional groups:
6. the method of claim 5, comprising one or more of the following features:
the structural formula of the aliphatic diamine isWherein a is a positive integer greater than or equal to 4;
the semi-aromatic nylon salt is obtained by reacting aromatic dibasic acid with first full-aliphatic diamine to form salt;
the full-aliphatic nylon salt is obtained by reacting full-aliphatic dibasic acid with second full-aliphatic diamine to form salt.
7. The method of claim 6, comprising one or more of the following features:
the aromatic dibasic acid is selected from one or two of terephthalic acid and isophthalic acid;
the full aliphatic dibasic acid is one or more compounds selected from the following structural compounds:
the first full aliphatic diamine is one or more compounds selected from the following structural compounds:
the second full aliphatic diamine is one or more compounds selected from the following structural compounds:
8. The method of claim 5, comprising one or more of the following features:
the end capping agent is one or more selected from benzoic acid, acetic acid, propionic acid and terephthalic acid;
the addition amount of the water is 2 to 15 weight percent of the mass of the semi-aromatic nylon salt;
the addition amount of the end-capping agent is 0.1-1 wt% of the mass of the semi-aromatic nylon salt.
9. The process according to claim 5, characterized in that the copolymerization is divided into three stages in sequence, according to the control of temperature and pressure:
the first stage is as follows: putting the component A, the semi-aromatic nylon salt and the full-aliphatic nylon salt into a reaction kettle, wherein the reaction temperature is 180-240 ℃, the preferable temperature is 190-210 ℃, and the reaction pressure is 1.5-2.5 MPa
And a second stage: the reaction temperature is 280-330 ℃, preferably 290-320 ℃, and the reaction pressure is 1.5-2.0 MPa
And a third stage: the reaction temperature is 280-330 ℃, preferably 290-320 ℃, the vacuum is realized, and the reaction pressure is-0.03-0.07 MPa.
10. Use of the copolymerized high temperature resistant nylon of any one of claims 1 to 4 in automotive engine peripheral parts.
Technical Field
The invention relates to a high molecular polymer, in particular to a copolymerization high temperature resistant nylon, a preparation method and application thereof.
Background
Polyamide (PA), commonly known as nylon, is a generic name for resins containing recurring amide groups in the molecular chain. The nylon is the basic resin with the maximum yield, the maximum variety, the widest application and the excellent comprehensive performance in five general engineering plastics. The high-temperature-resistant nylon is nylon engineering plastic which can be used at the temperature of more than 150 ℃ for a long time, and has good wear resistance, heat resistance, oil resistance, chemical resistance, dimensional stability and excellent mechanical property. The varieties which are industrialized at present are PA46, PA6T, PA9T, PA10T and the like. The Dutch DSM company in 1990 realizes the industrialization of the high temperature resistant nylon PA46 for the first time, and pulls open the curtain of the high temperature nylon research.
Chinese patent CN201510888782.1 discloses a bio-based high temperature resistant polyamide and a synthesis method thereof, aiming at the problem of over high melting point of the existing polyamide 6T resin, sebacic acid is added to reduce the melting point of a copolymer, polyester amide is added to improve the notch impact strength and antistatic capability of the copolymer, and N, N' -bis (2,2,6, 6-tetramethyl-4-piperidyl) -1, 3-benzene diamide is added to treat the yellowing problem in the polymerization process; the obtained bio-based high-temperature resistant polyamide has the characteristics of high mechanical property and heat resistance, low water absorption, excellent processing performance and biological source, and can be applied to the fields of electronic and electric appliances, LEDs, automobiles, aerospace, war industry and the like. However, N' -bis (2,2,6, 6-tetramethyl-4-piperidyl) -1, 3-benzene diamide is not directly connected to a bio-based high-temperature resistant polyamide macromolecular chain, and the durability of yellowing resistance is poor. Chinese patent CN201510750429.7 discloses a high molecular weight high temperature resistant polyamide resin and a preparation method thereof. The molecular main chain of the polyamide resin contains succinic acid units, and the relative viscosity of a solution with the concentration of 1.0g/dl prepared by using 96 wt% sulfuric acid as a solvent at 25 ℃ is 1.5-6.0; the melting point of the obtained polyamide resin is above 280 ℃. The preparation method related to the patent is to carry out transesterification reaction in the presence of a solvent, and the succinate ester has the problems of weak activity, low boiling point, easy volatilization and the like, and the polymerization process also has a series of problems of complex polymerization process, difficult industrial amplification and the like caused by amine transesterification reaction. The high-temperature nylon products in the current market have the problems of poor impact strength, low toughness, easy yellowing and the like due to the molecular chain structure.
Disclosure of Invention
In view of the above-mentioned disadvantages of the prior art, the present invention aims to provide a copolymerized high temperature resistant nylon, a preparation method and a use thereof, which are used for solving the problems in the prior art.
To achieve the above objects and other related objects, the present invention is achieved by the following technical solutions.
The invention provides a copolymerization high-temperature-resistant nylon, which is a nylon resin containing a repeating structural unit shown in a general formula (I), a repeating structural unit shown in a general formula (II) and a repeating structural unit shown in a general formula (III);
wherein a, b, c and d are all positive integers more than or equal to 4;
the structure of X is general formula (IV):
wherein R is selected from the following functional groups:
according to the technical scheme of the invention, in combination with the availability of raw materials and the condition of synthesis, preferably, a is 6, 9, 10 or 12, and the corresponding aliphatic diamine is one or more of hexamethylene diamine, nonane diamine, decamethylene diamine or dodecane diamine; b is 6, 9, 10 or 12, and the corresponding aliphatic diamine is one or more of hexamethylene diamine, nonane diamine, decamethylene diamine or dodecane diamine; c is 4, 8 or 10, and the corresponding aliphatic dibasic acid is one or more of adipic acid, sebacic acid or dodecanedioic acid; d is 6, 9 and 10, and the corresponding aliphatic diamine is one or more of hexamethylene diamine, nonane diamine, decamethylene diamine or dodecane diamine.
According to the technical scheme of the invention, the mass fraction of the repeating structural unit shown in the general formula (I) is 60-75%, the mass fraction of the repeating structural unit shown in the general formula (II) is 5-15%, and the mass fraction of the repeating structural unit shown in the general formula (III) is 10-35% on the basis of the total mass of the repeating units.
The invention also discloses a method for preparing the copolymerization high-temperature-resistant nylon, which comprises the following steps:
reacting dibasic acid with X structural characteristics with aliphatic diamine to form salt to obtain a component A;
then adding semi-aromatic nylon salt, full aliphatic nylon salt, water and a capping agent for copolymerization to obtain the product.
According to the technical scheme of the method, the dibasic acid with the structural feature of X is selected from one or more of the following structures:
wherein R is selected from the following functional groups:
according to the technical scheme of the method, the structural formula of the aliphatic diamine is shown in the specification
According to the technical scheme of the method, the semi-aromatic nylon salt is obtained by reacting aromatic dibasic acid with first full-aliphatic diamine to form salt.
According to the technical scheme of the method, the full-aliphatic nylon salt is obtained by reacting full-aliphatic dibasic acid with second full-aliphatic diamine to form salt.
According to the technical scheme of the method, the method comprises one or more of the following characteristics:
the aromatic dibasic acid is selected from one or two of terephthalic acid and isophthalic acid;
the full aliphatic dibasic acid is one or more compounds selected from the following structural compounds:
the above-mentionedThe first full aliphatic diamine is one or more compounds selected from the following structural compounds:
a is a positive integer greater than or equal to 4;
the second full aliphatic diamine is one or more compounds selected from the following structural compounds:
According to the technical scheme of the method, the addition amount of the water is 2-15 wt% of the mass of the semi-aromatic nylon salt.
According to the technical scheme of the method, the end-capping reagent is one or more of benzoic acid, acetic acid, propionic acid and terephthalic acid. Further, the addition amount of the end-capping agent is 0.1 wt% -1 wt% of the mass of the semi-aromatic nylon salt.
According to the technical scheme of the method, the copolymerization is carried out in an inert gas atmosphere. The inert gas is one of carbon dioxide, nitrogen, argon or helium.
According to the technical scheme of the method, the copolymerization time is at least 2 h.
According to the technical scheme of the method, the copolymerization is sequentially divided into three stages according to the control conditions of temperature and pressure:
the first stage is as follows: putting the component A, the semi-aromatic nylon salt and the full-aliphatic nylon salt into a reaction kettle, wherein the reaction temperature is 180-240 ℃, the preferable temperature is 190-210 ℃, and the reaction pressure is 1.5-2.5 MPa;
and a second stage: the reaction temperature is 280-330 ℃, preferably 290-320 ℃, and the reaction pressure is 1.5-2.0 MPa;
and a third stage: the reaction temperature is 280-330 ℃, preferably 290-320 ℃, the vacuum is realized, and the reaction pressure is-0.03-0.07 MPa.
The invention also discloses the application of the copolymerized high-temperature-resistant nylon in peripheral parts of an automobile engine.
The peripheral parts of the automobile engine comprise an exhaust control element, an oil filter, an engine and a starter shell.
Compared with the prior art, the invention has the beneficial effects that:
(1) the high-temperature-resistant nylon has highly symmetrical molecular structure and excellent thermal stability, and the diacid containing hindered piperidine amine is introduced into a nylon macromolecular chain to form the high-temperature-resistant nylon.
(2) The copolymerization high temperature resistant nylon molecular chain contains a large amount of secondary amine groups, has good dyeing property, and can obtain a series of deep-dyeable high temperature resistant nylons.
(3) The copolymerized high-temperature-resistant nylon has highly symmetrical molecular structure and excellent thermal stability, and diacid containing triazine rings and a large number of benzene ring structures is introduced into a nylon macromolecular chain, so that the obtained copolymerized nylon has higher glass transition temperature, higher char yield, lower water absorption and excellent flame retardant property.
Drawings
FIG. 1 shows an infrared spectrum of the copolymerized nylon of example 1 of the present invention.
Detailed Description
The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure.
Before the present embodiments are further described, it is to be understood that the scope of the invention is not limited to the particular embodiments described below; it is also to be understood that the terminology used in the examples is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention. Test methods in which specific conditions are not specified in the following examples are generally carried out under conventional conditions or under conditions recommended by the respective manufacturers.
When numerical ranges are given in the examples, it is understood that both endpoints of each of the numerical ranges and any value therebetween can be selected unless the invention otherwise indicated. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In addition to the specific methods, devices, and materials used in the examples, any methods, devices, and materials similar or equivalent to those described in the examples may be used in the practice of the invention in addition to the specific methods, devices, and materials used in the examples, in keeping with the knowledge of one skilled in the art and with the description of the invention.