WO2018133471A1

WO2018133471A1 - Carboxylated nitrile butadiene rubber grafted polyphenylene sulfide resin and synthetic method therefor

Info

Publication number: WO2018133471A1
Application number: PCT/CN2017/107616
Authority: WO
Inventors: 林良云; 易文彬; 周靖
Original assignee: 广州市鹏云工程塑料有限公司
Priority date: 2017-01-20
Filing date: 2017-10-25
Publication date: 2018-07-26
Also published as: CN106750346A; CN106750346B

Abstract

The present invention discloses a carboxylated nitrile butadiene rubber grafted polyphenylene sulfide resin, mainly prepared by a polymerization reaction of sodium sulfide, p-dichlorobenzene, lithium chloride, and carboxylated nitrile butadiene rubber. Further provided is a synthetic method for a carboxylated nitrile butadiene rubber grafted polyphenylene sulfide resin, comprising a dehydration processing process of sodium sulfide, a prepolymerization and polycondensation reaction process, a dehydration process of carboxylated nitrile butadiene rubber, a grafting and cross-linking process of the carboxylated nitrile butadiene rubber and a polyphenylene sulfide ether, and a discharging and washing process. The carboxylated nitrile butadiene rubber grafted polyphenylene sulfide resin of the present invention has an impact strength 20% to 50% higher than the impact strength of a polyphenylene sulfide that is not grafted with carboxylated nitrile butadiene rubber.

Description

Carboxyl nitrile rubber grafted polyphenylene sulfide resin and synthesis method thereof

Technical field

The invention relates to the field of polymer materials, in particular to a carboxylated nitrile rubber grafted polyphenylene sulfide resin and a synthesis method thereof.

Background technique

Polyphenylene sulfide (PPS) is a kind of thermoplastic crystalline resin with excellent performance. It can be combined with inorganic filler reinforced fiber to make PPS special engineering plastics. The advantages of PPS composites are high temperature resistance, corrosion resistance, radiation resistance, self-flame retardation, non-toxicity, dimensional stability, mechanical properties and electrical properties. At present, PPS composite materials have been widely used in many fields such as electronic appliances, automobiles, precision machinery, chemical industry and aerospace. Although it has many of the above advantages, there are still some features that do not meet the requirements for use in some special applications. Mainly manifested as: high brittleness and poor fatigue resistance. In order to improve these two obvious shortcomings of PPS composites, the common method is to use PPS resin and glass fiber. In the production process, tougheners (such as rubber, EBS, grafted PP, etc.) are added to improve Impact properties reduce their brittleness. This method has been widely used in practice, but the effect is still not ideal, because in the process of producing composite materials by twin-screw extruder, the molecular weight of rubber after shearing by twin-screw will be reduced by 20% to 40%, affecting The increase in toughness of the final PPS composite is still not ideal.

Summary of the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a carboxylated nitrile rubber grafted polyphenylene sulfide resin and a method for synthesizing the same to solve at least one of the above prior art problems.

According to an aspect of the present invention, a carboxylated nitrile rubber grafted polyphenylene sulfide resin is provided, which is mainly obtained by polymerizing sodium sulfide, p-dichlorobenzene, lithium chloride and carboxylated nitrile rubber.

The impact strength of the carboxylated nitrile rubber grafted polyphenylene sulfide resin of the present invention is 20% to 50% higher than that of the non-grafted carboxylated nitrile rubber.

In some embodiments, in terms of molar ratio, sodium sulfide 1, p-dichlorobenzene 1.02, lithium chloride 0.05 to 0.1; and parts by weight of p-dichlorobenzene 10, carboxylated nitrile rubber 1 to 6.

Another object of the present invention is to provide a method for synthesizing a carboxylated nitrile rubber grafted polyphenylene sulfide resin. The synthesis method comprises the following steps:

Step (1) Sodium sulfide dehydration treatment process: Proportionally weighed sodium sulfide and NMP solvent are added to the first reaction vessel, and sodium sulfide is dehydrated.

Step (2) Prepolymerization and polycondensation reaction process: the temperature of the first reaction vessel is raised to 155-165 ° C, and the proportionally-prepared p-dichlorobenzene and lithium chloride are added, and the dichlorobenzene and lithium chloride are sufficiently Dissolved in a solvent, the temperature of the reaction vessel was raised to 215 to 225 ° C and the polycondensation reaction was completed by heat preservation.

Step (3) Dehydration process of carboxylated nitrile rubber: adding a proportioned carboxylated nitrile rubber emulsion and NMP solvent to the second reaction vessel, dehydrating the carboxylated nitrile rubber emulsion to form a carboxylated nitrile rubber suspension .

Step (4) grafting and crosslinking process of the carboxylated nitrile rubber and the polyphenylene sulfide: the carboxylated nitrile rubber suspension prepared in the step (3) is added to the first reaction vessel, and the first reactor is heated to 260-270 The temperature is °C and the grafting and crosslinking process of the carboxylated nitrile rubber and the polyphenylene sulfide are completed.

Step (5) Discharge and washing process: the whole material in the first reaction kettle is subjected to solid-liquid separation, and the solid is carboxylated nitrile rubber grafted with polyphenylene sulfide and sodium chloride, and the sodium chloride is removed to obtain pure Carboxylated nitrile rubber grafted polyphenylene sulfide resin.

In some embodiments, wherein the lithium chloride added in step (2) is from 85 to 95% of the total lithium chloride content, the remaining lithium chloride is added in step (4). Lithium chloride is a highly active initiator. In the case of using the same amount of lithium chloride, lithium chloride is added twice, that is, after adding carboxylated nitrile rubber, a part of lithium chloride can be added to extend the chain. The grafting process is more complete. If all of the lithium chloride is added in the early stage of the reaction, after a few hours of reaction, the remaining active groups are all coated with the oligomer (i.e., the reaction product), and the activity is substantially lost.

In some embodiments, wherein, in step (1), the scaled sodium sulfide and NMP solvent are added to the first reactor with a condenser, and the first reactor is heated and maintained at 120-130 ° C. The sodium sulfide dehydration process is completed until the condenser outlet exits without water.

In some embodiments, wherein the temperature of the first reactor is raised to 155-165 ° C in step (2) and kept warm, and the proportionally-prepared p-dichlorobenzene and lithium chloride are added, and p-dichlorobenzene is added. Lithium chloride is sufficiently dissolved in the solvent, and the temperature of the first reactor is raised to 215 to 225 ° C and kept at a temperature of 1-3 ° C/min. Setting the reaction temperature to the above range at this stage makes the reaction more sufficient, and the polycondensation reaction is an exothermic reaction, and the temperature rise can be more controlled to better control the temperature of the reaction vessel. _

In some embodiments, wherein in step (3), a proportioned carboxylated nitrile rubber emulsion and NMP solvent are added to the second reactor with a stirred condenser, stirred and heated, and the temperature is raised to 115-125 ° C. Insulation, when the condenser has no water droplets, the dehydration process of the carboxylated nitrile rubber emulsion is completed, and a carboxylated nitrile rubber suspension is formed. The dehydration process of the carboxylated nitrile rubber emulsion can be efficiently performed.

In some embodiments, wherein the carboxylated nitrile rubber suspension prepared in the step (3) is added to the first reaction vessel in the step (4), the first reactor is heated to 260 to 270 ° C and kept warm to complete the carboxylated nitrile. Grafting and crosslinking process of rubber and polyphenylene sulfide. In the above temperature range, the group at the end of the carboxylated nitrile rubber is more active, which is more favorable for the reaction.

In some embodiments, wherein the first reactor is cooled to 75-85 ° C in step (5), and the whole material in the first reactor is subjected to solid-liquid separation through the step (4), and the solid is a carboxylated nitrile rubber. The polyphenylene sulfide and sodium chloride are grafted, and washed with deionized water to obtain a pure carboxylated nitrile rubber grafted polyphenylene sulfide resin. The advantage is that the operation is simple and easy.

In some embodiments, wherein steps (1) to (4) are carried out under the protection of nitrogen having a purity of 95% or more. Protection with high concentrations of nitrogen isolates the oxidation of oxygen from the air with the feedstock.

In some embodiments, wherein step (3) is carried out during the polycondensation reaction in step (2). Since the carboxylated nitrile rubber suspension prepared in the step (3) is precipitated for a long period of time, the carboxylated nitrile rubber precipitates, which is disadvantageous for the reaction of the step (4). The step (3) is carried out when the polycondensation reaction is carried out in the step (2), and the polycondensation reaction process in the step (2) can be completed substantially simultaneously with the dehydration process of the carboxylated nitrile rubber emulsion in the step (3), and the step (4) can be immediately entered.

detailed description

The invention is further illustrated by the following examples, but the scope of protection is not limited by the examples.

Example 1:

Step (1) Sodium sulfide dehydration process: In a 100 liter stainless steel first reactor with a condenser, 50 kg of NMP solvent (Chinese name: N-methyl-2-pyrrolidone) and 9.36 kg of sodium sulfide pentahydrate were added. After the addition was completed, nitrogen gas having a purity of 99.5% was passed for 2 to 3 minutes, and then the first reaction vessel was sealed. The temperature was raised to about 120 ° C while stirring, and maintained at this temperature, and the temperature increase rate was about 1 ° C / minute. During the heating process, the outlet of the condenser remains open, and there is a continuous flow of liquid. This is the crystal water contained in the sodium sulfide pentahydrate. When there is no liquid flowing out of the condenser outlet, the condenser outlet is closed, and the sodium sulfide is closed. The dehydration process is complete.

Step (2) Prepolymerization and polycondensation reaction process: the temperature of the first reaction kettle is raised to about 160 ° C, and the temperature increase rate may be about 4 ° C / minute. After reaching the set temperature, 10.8 kg of p-dichlorobenzene and 0.3 kg are added. Lithium chloride. After the completion of the addition, the temperature in the autoclave was maintained at about 160 ° C for 0.5 to 1.5 hours to sufficiently dissolve the p-dichlorobenzene and lithium chloride in the solvent. The temperature was raised to 220 ° C and maintained. The temperature increase rate was set to about 2 ° C / min, the temperature rise time was about 0.5 to 1 hour, and the reaction was carried out at this temperature for about 3.5 hours to complete the polycondensation reaction process.

Step (3) Dehydration process of carboxylated nitrile rubber: while the material of the first reactor is subjected to polycondensation reaction, another 50 liter stainless steel second reaction vessel with condenser is added, and 2.16 kg of carboxylated nitrile rubber emulsion is added. (Because the unvulcanized rubber can only maintain fine particles in the emulsion state, the solid content of the carboxylated nitrile rubber is 50%), 5 kg of NMP solvent is added, and the temperature is raised while stirring (stirring speed 200 rpm), and the heating rate is 1 ° C / Minutes, while opening the condenser outlet, at During the heating process, the liquid gradually flows out. This is the water in the emulsion. After rising to 120 °C, the temperature is stopped and kept warm until there is no water drop at the outlet. This process produces a carboxylated nitrile rubber suspension.

Step (4) Grafting and crosslinking process of polyphenylene sulfide: after the polycondensation reaction is completed in the first reactor, the carboxylated nitrile obtained in the step (3) is prepared by the high temperature and high pressure conveying device after the polycondensation reaction is completed in the step (2). The rubber suspension and 50 g of lithium chloride were added to the first reaction vessel, and then the temperature was raised. The temperature was raised to 2 ° C / min, and the temperature was raised to 265 ° C and held for 2 hours.

Step (5) The first reaction vessel is cooled to about 80 ° C, and all the materials in the first reaction vessel through the step (4) are subjected to solid-liquid separation, the liquid is a solvent and an oligomer, and the solid is a carboxylated nitrile rubber graft. Polyphenylene sulfide and sodium chloride, the solid is washed with deionized water to obtain a pure carboxylated nitrile rubber grafted polyphenylene sulfide resin.

Online infrared monitoring system control is used throughout the synthesis system process. During the feeding operation in the middle of the reaction, the materials were all completed under the protection of nitrogen with a purity of 99.5%. Among them, the NMP solvent is an industrial grade raw material with a purity of 99.5%, and the p-dichlorobenzene is an industrial grade raw material with a purity of 99.3%. Step (3) can also be carried out simultaneously in the latter stage of step (2), because the carboxylated nitrile rubber suspension prepared in the step (3) is precipitated if the carboxylation of the carboxylated nitrile rubber is too long, which is disadvantageous for the step (4). reaction.

Sodium sulfide is very easy to absorb water, it is difficult to exist in the form of pure sodium sulfide in the air. In industrial production, sodium sulphate is used in the production of sodium sulphate, and the content of sodium sulphide is determined before feeding to ensure the accuracy of feeding. In the present example, 9.36 kg of sodium sulfide pentahydrate was added, and the raw material had a sodium sulfide content of 60%. In other embodiments, sodium sulfide in the form of sodium hesitate heptahydrate or the like may also be employed.

In the present embodiment, the carboxylated nitrile rubber is a carboxylated nitrile rubber emulsion having a solid content of 50%. In other embodiments, the solids may be other percentages of carboxylated nitrile rubber emulsions.

In terms of molar ratio, sodium sulfide 1, p-dichlorobenzene 1.02, lithium chloride 0.05 to 0.1. When the raw material uses sodium sulfide pentahydrate having a sodium sulfide content of 60%, the above three molar ratios of the raw materials are converted into weight ratios, wherein sodium sulfide pentahydrate 1, p-dichlorobenzene 1.15, lithium chloride 0.03 ~ 0.05.

In other embodiments, the reaction temperature parameter and the time parameter and the like can be adjusted within a certain range:

The dehydration temperature of the sodium sulfide in the step (1) may be 120 to 130 °C.

The dissolution temperature of the p-dichlorobenzene and the lithium chloride in the step (2) may be 155 to 165 ° C, the polycondensation reaction temperature may be 215 to 225 ° C, and the reaction time may be 4 to 5 hours to ensure that the polycondensation reaction is complete.

The dehydration temperature of the carboxylated nitrile rubber in the step (3) may be from 115 to 125 °C.

The reaction temperature of the step (4) may be 260 to 270 ° C, and the reaction time may also be set according to the actual feeding condition to ensure that the reaction is complete.

The solid-liquid separation temperature of the step (5) may be from 75 to 85 °C.

The purity of nitrogen can be 95% or more.

The capacity of the first reactor and the second reactor can be selected depending on how much material is charged.

Examples 1 to 10 in Table 1 are examples in which a carboxylated nitrile rubber-grafted polyphenylene sulfide resin was prepared in the same manner as in Example 1, sodium pentasulfate pentahydrate, p-dichlorobenzene, lithium chloride and carboxyl groups. The amount of nitrile rubber sodium sulfide emulsion charged. Examples 11 to 20 are raw material amounts of all of the lithium chloride added to the synthesized carboxylated nitrile rubber-grafted polyphenylene sulfide resin in the step (2). Examples 21 to 30 are the amounts of the polyphenylene sulfide resin to which the carboxylated nitrile rubber is not added.

Table 2 shows the results of performance tests on the carboxylated nitrile rubber grafted polyphenylene sulfide resin prepared in the examples described in Table 1.

It can be seen from Table 1 and Table 2:

Carboxy-butyronitrile rubber was added to all of Examples 1 to 20, and the physical properties and mechanical properties of the products were significantly higher than those of Examples 21 to 30 (without addition of carboxylated nitrile rubber), and the melting point was also higher, indicating carboxyl butyronitrile. The rubber-grafted polyphenylene sulfide resin has better high temperature resistance.

The overall performance of Example 2 was optimized, indicating that the amount of each component charged in this example was the most suitable.

The physical properties and mechanical properties of the products of Examples 1 to 10 were significantly higher than those of Examples 11 to 20, indicating that lithium chloride was added in two portions, that is, after adding carboxylated nitrile rubber, a small portion of lithium chloride was added to make carboxylated n. The chain extension and grafting process of rubber and polyphenylene sulfide is more complete.

Carboxylated nitrile rubber grafted polyphenylene sulfide resin can be widely used in many fields such as electronic appliances, automobiles, precision machinery, chemical industry and aerospace.

What has been described above is only some embodiments of the invention. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and scope of the invention.

Table 1:

Table 2:

Claims

A carboxylated nitrile rubber grafted polyphenylene sulfide resin, which is mainly obtained by polymerization of sodium sulfide, p-dichlorobenzene, lithium chloride and carboxylated nitrile rubber.
The carboxylated nitrile rubber-grafted polyphenylene sulfide resin according to claim 1, wherein the sodium sulfide, p-dichlorobenzene 1.02, lithium chloride is 0.05 to 0.1 in terms of a molar ratio, and parts by weight, Wherein the p-dichlorobenzene 10 and the carboxylated nitrile rubber are 1 to 6.
The method for synthesizing a carboxylated nitrile rubber grafted polyphenylene sulfide resin comprises the following steps:

Step (1) sodium sulfide dehydration treatment process: proportionally weighed sodium sulfide and NMP solvent are added to the first reaction kettle, and the sodium sulfide is dehydrated;

Step (2) prepolymerization and polycondensation reaction process: adding proportionally good p-dichlorobenzene and lithium chloride in the first reaction kettle, and completely dissolving the dichlorobenzene and lithium chloride in the solvent, first The temperature of the reaction vessel is raised to 215 to 225 ° C and kept warm to complete the polycondensation reaction;

Step (3) Dehydration process of carboxylated nitrile rubber: adding a proportioned carboxylated nitrile rubber emulsion and NMP solvent to the second reaction vessel, dehydrating the carboxylated nitrile rubber emulsion to form a carboxylated nitrile rubber suspension ;

Step (4) grafting and crosslinking process of the carboxylated nitrile rubber and the polyphenylene sulfide: the carboxylated nitrile rubber suspension prepared in the step (3) is added to the first reaction vessel, and the first reactor is heated to 260. 270 ° C and heat preservation, complete the grafting and crosslinking process of carboxylated nitrile rubber and polyphenylene sulfide;

Step (5) Discharge and washing process: the whole material in the first reaction kettle is subjected to solid-liquid separation, the solid is carboxylated nitrile rubber grafted polyphenylene sulfide and sodium chloride, and the sodium chloride is removed to obtain carboxylate Nitrile rubber grafted polyphenylene sulfide resin.
The synthesis method according to claim 3, wherein in the step (1), the scaled sodium sulfide and NMP solvent are added to the first reactor with a condenser, and the first reactor is heated and maintained at 120. Between ~130 ° C, until the outlet of the condenser is no longer flowing out, the sodium sulfide dehydration process is completed.
The synthesis method according to claim 3, wherein in the step (2), the temperature of the first reactor is raised to 155 to 165 ° C and kept warm, and the proportionally-prepared p-dichlorobenzene and lithium chloride are added. The dichlorobenzene and lithium chloride are sufficiently dissolved in the solvent, and the temperature of the first reactor is gradually raised to 215 to 220 ° C and kept warm to complete the polycondensation reaction, and the temperature rising rate is 1 to 3 degrees/min.
The synthesis method according to claim 3, wherein in the step (3), a proportioned carboxylated nitrile rubber emulsion and an NMP solvent are added to the second reactor with a stirring condenser, stirred and heated, and heated. It is heated to 115-125 ° C and the dehydration process of the carboxylated nitrile rubber emulsion is completed when the condenser has no water droplets, forming a carboxylated nitrile rubber suspension.
The synthesis method according to claim 3, wherein in the step (5), the first reactor is cooled to 75 to 85 ° C, and all the materials in the first reactor through the step (4) are subjected to solid-liquid separation. The solid is a carboxylated nitrile rubber grafted with polyphenylene sulfide and sodium chloride, and washed with deionized water to obtain a carboxylated nitrile rubber grafted polyphenylene sulfide resin.
The synthesis method according to any one of claims 3 to 7, wherein the lithium chloride added in the step (2) is 85 to 95% of the total lithium chloride content, and the remaining lithium chloride is added in the step (4).
The synthesis method according to any one of claims 3 to 7, wherein the steps (1) to (4) are carried out under the protection of nitrogen having a purity of 95% or more.
The synthesis method according to any one of claims 3 to 7, wherein the step (3) is carried out when the polycondensation reaction is carried out in the step (2).