阅读说明：本技术 一种生物基高温尼龙的制备方法 (Preparation method of bio-based high-temperature nylon ) 是由 陈林飞 陈培 路丹 叶耀挺 于 2019-08-19 设计创作，主要内容包括：本发明公开了一种生物基高温尼龙的制备方法,包含：(1)将混合二酸、戊二胺、醇类溶剂及催化剂、封端剂加入反应釜中,用氮气置换釜内空气后,打开加热,在170-200℃下保持1-2h,降温并过滤或离心,溶剂回收,得到白色粉状预聚物；(2)将步骤(1)中得到的白色粉状预聚物放入至真空转鼓中,并加入热稳定剂,抽真空,打开加热,在220-260℃下反应6-8h；降温出料得到白色聚合物,即生物基高温尼龙。本发明中,选用混合二酸、戊二胺作为反应原料,结合特定的反应溶剂(醇类溶剂),能够在要求更低的条件下制备出性能更加优异的生物基高温尼龙。(The invention discloses a preparation method of bio-based high-temperature nylon, which comprises the following steps: (1) adding mixed diacid, pentanediamine, an alcohol solvent, a catalyst and an end-capping reagent into a reaction kettle, replacing air in the kettle with nitrogen, opening and heating, keeping the temperature for 1-2h at the temperature of 170-200 ℃, cooling, filtering or centrifuging, and recovering the solvent to obtain a white powdery prepolymer; (2) putting the white powdery prepolymer obtained in the step (1) into a vacuum drum, adding a heat stabilizer, vacuumizing, opening and heating, and reacting at the temperature of 220-; cooling and discharging to obtain the white polymer, namely the bio-based high-temperature nylon. According to the invention, mixed diacid and pentanediamine are selected as reaction raw materials, and a specific reaction solvent (alcohol solvent) is combined, so that the bio-based high-temperature nylon with more excellent performance can be prepared under the condition of lower requirements.)

1. The preparation method of the bio-based high-temperature nylon is characterized by comprising the following steps:

(1) adding mixed diacid, pentanediamine, an alcohol solvent, a catalyst and an end-capping reagent into a reaction kettle, replacing air in the kettle with nitrogen, filling nitrogen to keep the pressure in the kettle at 0.05-0.1MPa, opening and heating, raising the temperature in the kettle to 170-200 ℃, keeping the temperature at 170-200 ℃ for 1-2h, cooling, filtering or centrifuging, and recovering the solvent to obtain a white powdery prepolymer;

(2) and (2) putting the white powdery prepolymer obtained in the step (1) into a vacuum drum, adding a heat stabilizer, vacuumizing, opening and heating, raising the temperature to 260 ℃ below the temperature of 220-.

2. The method for preparing bio-based high temperature nylon according to claim 1, wherein in step (1), the mixed diacid is at least two of terephthalic acid, adipic acid, isophthalic acid and furandicarboxylic acid.

3. The method for preparing bio-based high temperature nylon according to claim 1, wherein in the step (1), the alcohol solvent is ethanol.

4. The method as claimed in claim 1, wherein in step (1), the catalyst is sodium hypophosphite, potassium hypophosphite, sodium hypophosphite, magnesium hypophosphite, calcium hypophosphite or zinc hypophosphite.

5. The method for preparing bio-based high temperature nylon according to claim 1, wherein in the step (1), the end-capping reagent is any one of benzoic acid, naphthoic acid, methylnaphthoic acid and phenylacetic acid.

6. The preparation method of bio-based high temperature nylon according to claim 1, wherein in steps (1) and (2), the mixed diacid, the pentanediamine, the alcohol solvent, the catalyst, the end-capping agent and the heat stabilizer are in parts by weight: 40-80 parts of mixed diacid: 30-50 parts of pentamethylene diamine: 200-500 parts of an alcohol solvent: 0.1-5 parts of a catalyst: 0.1-5 parts of end-capping agent: 0.1-5 parts of a heat stabilizer.

7. The method for preparing bio-based high temperature nylon according to claim 1, wherein in the step (1), the air in the autoclave is replaced with nitrogen three times.

8. The method for preparing bio-based high temperature nylon according to claim 1, wherein in the step (1), the temperature in the kettle is raised to 190 ℃ and is maintained at 190 ℃ for 1 h.

9. The method for preparing bio-based high temperature nylon according to claim 1, wherein in the step (2), the temperature is raised to 230 ℃ and the reaction is carried out for 6h at 230 ℃.

10. The method for preparing bio-based high temperature nylon according to claim 1, wherein in the step (2), the heat stabilizer is any one of copper chloride, copper bromide, copper iodide, copper dichloride, copper dibromide, copper diiodide and copper phosphate.

Technical Field

The invention relates to the field of preparation of high-temperature nylon, in particular to a preparation method of bio-based high-temperature nylon.

Background

The high-temperature nylon is high-heat-resistance resin between general engineering plastic nylon and high-temperature-resistant engineering plastic PEEK, and is widely applied to the fields of electronic and electrical industry, automobile industry and the like. The material has excellent comprehensive properties, such as: short-term and long-term heat resistance, high rigidity, creep resistance at high temperature, outstanding toughness, excellent fatigue resistance, good chemical resistance.

Domestic and foreign patents such as CN102153741A, CN101289535A, CN1012153751A, CN102477219A, US4603166, US4076664, US4762910, US6518341, US6747120, US4246395 and the like disclose preparation methods of high-temperature nylon, and methods of prepolymerization and then polymerization are mostly adopted, and a solid-phase or reactive screw extruder is generally adopted for the post polymerization to improve the molecular weight, wherein the prepolymerization process is the most critical and influences the final quality of products. In addition, most of domestic and foreign related enterprises still adopt petroleum-based raw materials to prepare high-temperature nylon, and sustainable development is not achieved.

After the twenty-first century, human beings are puzzled by energy and environmental problems, and in order to realize sustainable, green and environment-friendly development of macromolecules and related fine chemical industries, bio-based raw materials capable of replacing the existing petroleum are searched globally, so that the dependence on the petroleum is reduced, the national energy safety is improved, the pollution of the petroleum industry to the environment is reduced, and the common 'home' and earth are protected.

In recent years, the increase of the content of the bio-based materials is a new trend of being environment-friendly high polymer materials, and the preparation of the bio-based nylon by using biomass as a raw material, especially the bio-based high temperature nylon, is a hot point of domestic and foreign research and is a direction of future development of the high temperature nylon. China is in the same starting line with the renewable bio-based high-temperature nylon at abroad, and if the China actively advances, the situation that the current monopoly of petroleum-based high-temperature-resistant nylon is broken is expected to break, and the China is in the international leading level.

The bio-based pentanediamine is produced by renewable raw materials and a biological fermentation process, and compared with the existing production process of hexanediamine, the production process of the pentanediamine can obviously reduce the carbon footprint. At present, the domestic production is realized, the yield is sufficient, the price is equivalent to that of hexamethylene diamine, and the biogenic amine has excellent cost performance. The pentamethylene diamine is used as the matrix to prepare the novel high-performance bio-based high-temperature nylon.

Disclosure of Invention

The invention provides a preparation method of bio-based high-temperature nylon, which takes pentanediamine as a substrate to prepare the bio-based high-temperature nylon through copolymerization. Provides a new idea and a new method for preparing the high-temperature nylon resin, and is suitable for industrialization.

A preparation method of bio-based high-temperature nylon comprises the following steps:

(1) adding mixed diacid, pentanediamine, an alcohol solvent, a catalyst and an end-capping reagent into a reaction kettle, replacing air in the kettle with nitrogen, filling nitrogen to keep the pressure in the kettle at 0.05-0.1MPa, opening and heating, raising the temperature in the kettle to 170-200 ℃, keeping the temperature at 170-200 ℃ for 1-2h, cooling, filtering or centrifuging, and recovering the solvent to obtain a white powdery prepolymer;

(2) putting the white powdery prepolymer obtained in the step (1) into a vacuum drum, adding a heat stabilizer, vacuumizing, opening and heating, raising the temperature to 260 ℃ of 220-; cooling and discharging to obtain the white polymer, namely the bio-based high-temperature nylon.

According to the invention, mixed diacid and pentanediamine are selected as reaction raw materials, and a specific reaction solvent (alcohol solvent) is combined, so that the bio-based high-temperature nylon with more excellent performance can be prepared under the condition of lower requirements.

In the step (1), the mixed diacid is at least two of terephthalic acid, adipic acid, isophthalic acid and furandicarboxylic acid.

The alcohol solvent is ethanol.

The catalyst is sodium hypophosphite, potassium hypophosphite, sodium hypophosphite, magnesium hypophosphite, calcium hypophosphite or zinc hypophosphite, and preferably sodium hypophosphite.

The end-capping reagent comprises any one of benzoic acid, naphthoic acid, methylnaphthoic acid and phenylacetic acid, and preferably benzoic acid.

The mixed diacid, the pentanediamine, the alcohol solvent, the catalyst, the end-capping agent and the heat stabilizer comprise the following components in percentage by mass: 40-80 parts of mixed diacid: 30-50 parts of pentamethylene diamine: 200-500 parts of an alcohol solvent: 0.1-5 parts of a catalyst: 0.1-5 parts of end-capping agent: 0.1-5 parts of a heat stabilizer.

More preferably, the mixed diacid, the pentanediamine, the alcohol solvent, the catalyst, the end-capping agent and the heat stabilizer are in mass fraction: 50-70 parts of mixed diacid: 35-45 parts of pentamethylene diamine: 200-400 parts of an alcohol solvent: 0.1-5 parts of a catalyst: 0.1-5 parts of end-capping agent: 0.1-5 parts of a heat stabilizer.

The air in the kettle was replaced with nitrogen three times.

Still more preferably, the temperature in the vessel is raised to 190 ℃ and maintained at 190 ℃ for 1 hour.

The reaction formula is as follows:

in the step (2), the vacuum is pumped to 0-50 Pa, and preferably to 20 Pa.

The temperature is increased to 230 ℃, and the reaction is carried out for 6h at 230 ℃;

the heat stabilizer comprises any one of copper chloride, copper bromide, copper iodide, copper dichloride, copper dibromide, copper diiodide and copper phosphate, and preferably copper iodide.

In the preparation method (1), the prepolymerization temperature is controlled to be between 170 ℃ and 220 ℃ and lower than 170 ℃, the reaction monomers cannot be effectively converted into prepolymers, the temperature is too high, the pressure in the reactor is too high, the requirement on equipment is high, and side reactions are easy to occur.

Compared with the prior art, the invention has the following advantages:

firstly, the bio-based reaction monomer pentanediamine is used as a substrate to prepare the bio-based high-temperature nylon with a novel chemical structure through copolymerization, and the prepared bio-based high-temperature nylon has more excellent performance.

Secondly, alcohol is used as a reaction solvent, and a specific reactant (mixed diacid and 1, 5-pentanediamine) is combined, so that a chemical reaction can be carried out at a low temperature (below 200 ℃), a prepolymer is promoted to be generated, the requirement on equipment is not high, the energy consumption of the reaction is low, the alcohol solvent can be mutually dissolved with water generated in the reaction, the polycondensation reaction is accelerated to be carried out in the positive direction, the obtained prepolymer is powdery, and the discharge is convenient.

Drawings

FIG. 1 is an infrared spectrum of bio-based high temperature nylon obtained in example 1;

FIG. 2 is a DSC (Differential scanning calorimetry) curve of the bio-based high temperature nylon obtained in example 1;

FIG. 3 is a DSC curve of high temperature nylon PA6T prepared using 1, 6-hexanediamine.

Detailed Description

The following examples and comparative examples illustrate the present invention by way of illustration and explanation of the synthetic process, but do not limit the scope of the invention.

1. Intrinsic viscosity [ eta ]

The nylon tested was dissolved in concentrated sulfuric acid to give concentrations of 1g/dl, 0.8g/dl, 0.6g/dl, 0.4g/dl, 0.2g/dl, respectively, and the logarithmic viscosity η inh of the solution was measured at 25 ℃:

ηinh＝[ln(t1/t0)]/C

where t0 represents the time(s) of solvent outflow, t1 represents the time(s) of sample solution outflow, C represents the concentration (g/dl) of the sample solution, and η inh represents the logarithmic viscosity number (dl/g).

Extrapolating the data of η inh to a concentration of 0 to obtain the intrinsic viscosity of the sample.

2. Melting Point

The melting point of the sample was measured using a Mettler-Toriledo DSC1 apparatus, and the temperature was raised from room temperature to 330 ℃ at 10 ℃/min under nitrogen atmosphere for 5min, then cooled at 10 ℃/min to room temperature, and then raised at 10 ℃/min to 330 ℃ at which the endothermic peak temperature was the polymer melting point.

3. Mechanical properties

The prepared nylon injection molding test sample bar is tested for tensile strength according to the GB/T1040.2 standard, bending strength and bending modulus according to the GB/T9341-2008 standard, and impact strength of a simply supported beam according to the GB/T1043.1 standard.