CN110950978A

CN110950978A - Preparation method of brominated polystyrene with high thermal stability

Info

Publication number: CN110950978A
Application number: CN201911119296.8A
Authority: CN
Inventors: 郭建树; 赵震; 王盛海
Original assignee: Shandong Meite New Material Technology Co Ltd
Current assignee: Shandong Meite New Material Technology Co Ltd
Priority date: 2019-11-15
Filing date: 2019-11-15
Publication date: 2020-04-03

Abstract

The invention discloses a synthesis method of Brominated Polystyrene (BPS) with high thermal stability, which utilizes the mechanism that active functional groups of organic matters are easy to react with bromine/HBr to remove aliphatic bromine on BPS molecular chains by reacting with common BPS, and bonds the removed bromine elements to self molecules through chemical bonds to generate a BPS flame retardant with high thermal stability, wherein the BPS flame retardant prepared by the invention has high decomposition temperature and good thermal stability, the 1 percent TGA thermal weight loss temperature is more than or equal to 350 ℃, and the PA66 flame retardant resin prepared by the BPS flame retardant shows excellent color stability and thermal stability under high temperature and high shear, and the 1 percent TGA thermal weight loss temperature is more than or equal to 360 ℃.

Description

Preparation method of brominated polystyrene with high thermal stability

Technical Field

The invention relates to a chemical synthesis method for preparing a Brominated Polystyrene (BPS) flame retardant with high thermal stability, belonging to the technical field of preparing flame retardant materials by using the chemical synthesis method.

Background

Brominated polystyrene has the advantages of moderate molecular weight, good thermal stability, good dispersibility and compatibility in high polymers, easy processing, no blooming and the like, is widely used in thermoplastic plastics such as PE, PP, ABS, HIPS, PBT, PET, nylon, thermoplastic polyurethane and the like and PC/ABS plastic alloy, and has huge market capacity.

At present, there are two main synthetic methods, which are respectively a process of bromination first and then polymerization represented by the company Kehai of America, and the process is completed by three steps of reaction, firstly β -bromoethylbenzene is subjected to benzene ring bromination to generate polybrominated β -bromoethylbenzene, the polybrominated β -bromoethylbenzene eliminates fatty bromine under the action of alcohol alkali to generate polybrominated polystyrene which can be polymerized, and then the polybrominated polystyrene with proper molecular weight is produced by polymerization.

The other is a process of polymerization and bromination firstly represented by the American Abboto company, which uses anion PS specially supplied for DOW as a base material to synthesize BPS by bromination, the molecular weight of the anion PS is easy to control, the structure is regular, the molecular chain of a Bromination Product (BPS) has less fat substituted bromine, the thermal decomposition temperature is high, but the production environment of the anion PS is harsh, the using amount of an initiator is large, and the cost is high.

Although general-purpose GPPS (i.e. general-purpose polystyrene, PS for short, is polymerized from styrene monomer SM, and can be polymerized by various synthesis methods) is low in cost and easy to purchase, brominated polystyrene synthesized by the general-purpose GPPS has higher content of aliphatic substituted bromine on a main chain of BPS macromolecules synthesized by bromination of anionic PS, and has poor thermal stability. It has been reported that strong base can be used to remove HBr on the macromolecular chain, so as to reduce the content of fatty bromine and improve the thermal stability of BPS. However, the HBr removing process is complicated, the pollution is serious, and the effect is not outstanding. It has also been reported that the addition of high performance heat stabilizers or antioxidants to the BPS increases the thermal stability of the BPS, but it is not desirable in real application environments.

The invention relates to a high-thermal-stability Brominated Polystyrene (BPS) flame retardant, which is prepared by taking BPS prepared by general GPPS as a reaction substrate and taking a polymer containing active functional groups as a halogen absorbent to react to prepare the high-thermal-stability BPS flame retardant.

Disclosure of Invention

The invention aims to prepare high-thermal-stability BPS (brominated polystyrene) flame retardant by a simple and efficient method, wherein BPS prepared by taking general PS as a raw material is taken as a reaction substrate, a polymer containing active functional groups is taken as a halogen absorbent, fatty bromine on a BPS molecular chain is removed at a higher temperature, and the removed bromine is bonded to a self molecule through a chemical bond to generate the high-thermal-stability Brominated Polystyrene (BPS) flame retardant.

The invention relates to a preparation method of a Brominated Polystyrene (BPS) flame retardant with high thermal stability, which is produced according to the following process: the anhydride compound containing active functional groups is uniformly mixed with BPS solid powder according to a certain proportion, and the mixture reacts in a blast drying oven or a high-speed mixer for a certain time at a certain temperature to generate the brominated polystyrene flame retardant with high thermal stability.

Preferably, the acid anhydride compound containing active functional groups in the reaction is one or more of maleic anhydride, phthalic anhydride and octenyl succinic anhydride.

Preferably, the acid anhydride compound containing active functional groups in the reaction accounts for 0.2 to 5 percent of the weight of the BPS solid powder, and preferably 0.5 to 2 percent.

Preferably, the reaction temperature is 100 ℃ to 150 ℃, more preferably 120 ℃ to 130 ℃.

Preferably, the reaction time is 2 to 24 hours, more preferably 4 to 6 hours.

The BPS flame retardant prepared by the invention has high decomposition temperature and good thermal stability, the 1% TGA thermal weight loss temperature is more than or equal to 350 ℃, the PA66 flame-retardant resin prepared by the BPS flame retardant shows excellent color stability and thermal stability under high temperature and high shear, and the 1% TGA thermal weight loss temperature is more than or equal to 360 ℃.

Detailed Description

Example 1

Uniformly mixing 1g of maleic anhydride and 200g of common brominated polystyrene, heating and reacting for 4 hours in a forced air drying oven at the temperature of 120-125 ℃, and cooling to obtain 200g of brominated polystyrene with high thermal stability, wherein the thermal weight loss temperature of 1 percent TGA is 341 ℃; 180g of BPS of this example was added to PA66 resin containing 30% glass fibers and 6% antimony trioxide, and the flame retardant resin was prepared by high temperature shearing at 1% TGA thermogravimetric temperature 361 ℃ and was white in color.

Example 2

Uniformly mixing 2g of maleic anhydride and 200g of common brominated polystyrene, heating and reacting for 4 hours in a forced air drying oven at the temperature of 120-125 ℃, and cooling to obtain 201g of brominated polystyrene with high thermal stability, wherein the thermal weight loss temperature of 1% TGA is 342 ℃; 180g of BPS of this example was added to PA66 resin containing 30% glass fibers and 6% antimony trioxide, and the resulting flame retardant resin was sheared at high temperature to give a 1% TGA thermogravimetric temperature of 363 ℃ and a white color.

Example 3

Uniformly mixing 1g of maleic anhydride and 200g of common brominated polystyrene, heating and reacting for 4 hours in a forced air drying oven at the temperature of 140-145 ℃, and cooling to obtain 200g of brominated polystyrene with high thermal stability, wherein the thermal weight loss temperature of 1% TGA is 341 ℃; 180g of BPS of this example was added to PA66 resin containing 30% glass fibers and 6% antimony trioxide, and the flame retardant resin was prepared by high temperature shearing at 1% TGA thermogravimetric temperature 367 ℃ and was white in color.

Example 4

Uniformly mixing 1g of maleic anhydride and 200g of common brominated polystyrene, heating and reacting for 6 hours in a forced air drying oven at 100-115 ℃, and cooling to obtain 200g of brominated polystyrene with high thermal stability, wherein the thermal weight loss temperature of 1% TGA is 340 ℃; 180g of BPS of this example was added to PA66 resin containing 30% glass fibers and 6% antimony trioxide, and the resulting flame retardant resin was sheared at high temperature to give a 1% TGA thermogravimetric temperature of 363 ℃ and a white color.

Example 5

Uniformly mixing 1g of maleic anhydride and 200g of common brominated polystyrene, heating and reacting for 24 hours in a forced air drying oven at the temperature of 120-125 ℃, and cooling to obtain 200g of brominated polystyrene with high thermal stability, wherein the thermal weight loss temperature of 1% TGA is 343 ℃; 180g of BPS of this example was added to PA66 resin containing 30% glass fibers and 6% antimony trioxide, and the flame retardant resin was prepared by high temperature shearing at 1% TGA thermogravimetric temperature 365 ℃ and was white in color.

Example 6

Uniformly mixing 4g of isoprene with 200g of ordinary brominated polystyrene, heating and reacting for 4 hours in a forced air drying oven at the temperature of 120-125 ℃, and cooling to obtain 203g of brominated polystyrene with high thermal stability, wherein the thermal weight loss temperature of 1% TGA is 343 ℃; 180g of BPS of this example was added to PA66 resin containing 30% glass fibers and 6% antimony trioxide, and the flame retardant resin was prepared by high temperature shearing at 1% TGA thermogravimetric temperature 367 ℃ and was white in color.

Comparative example

Ordinary brominated polystyrene, wherein the 1 percent TGA thermal weight loss temperature is 321 ℃; 180g of common BPS is added into PA66 resin containing 30 percent of glass fiber and 6 percent of antimony trioxide, and the flame-retardant resin prepared by high-temperature shearing has the thermal weight loss temperature of 1 percent TGA of 341 ℃ and the color of the resin is yellow.

Claims

1. A preparation method of brominated polystyrene with high thermal stability is characterized by comprising the following steps: mixing an anhydride compound containing active functional groups with BPS solid powder, and reacting at a certain temperature to generate the brominated polystyrene flame retardant with high thermal stability.

2. The method for preparing brominated polystyrene with high thermal stability according to claim 1, wherein the acid anhydride compound containing active functional groups is one or more of maleic anhydride, phthalic anhydride and octenyl succinic anhydride.

3. The method of claim 1, wherein the acid anhydride compound is 0.2-5%, preferably 0.5-2% by weight of the BPS solid powder.

4. The method for preparing brominated polystyrene with high thermal stability according to claim 1, wherein the reaction temperature is 100 ℃ to 150 ℃, preferably 120 ℃ to 130 ℃.

5. The process for preparing brominated polystyrene with high thermal stability according to claim 1, wherein the reaction time is 2 to 24 hours, preferably 4 to 6 hours.

6. A brominated polystyrene of high thermal stability, obtainable by a process according to any one of claims 1 to 5.

7. A flame-retardant PA66 resin, characterized in that it is produced using the high-thermal-stability brominated polystyrene of claim 6 as a flame retardant.