The Production Process Of ABS Polyresin

- Mar 19, 2018 -

The production process of ABS Polyresin





1.jpg

There are many industrial production methods for ABS, such as emulsion grafting, emulsion grafting, and law enforcement. The emulsion grafting method is an ABS resin obtained by grafting styrene monomer and acrylonitrile onto a polybutadiene latex. This method has now been replaced by emulsion grafting. Emulsion grafting and doping is developed on the basis of the traditional method of ABS resin--emulsion grafting method. It will partially graft styrene monomer and acrylonitrile and polybutadiene latex by emulsion graft copolymerization.

A portion of the styrene monomer and acrylonitrile monomer are copolymerized to form SAN, and then the two are blended in different ratios to obtain various grades of ABS resin. The specific process of ABS resin is as follows: Synthesis of butadiene latex; Auxiliary solution consisting of emulsifier potassium oleate, mercaptan, potassium persulfate, etc. is added to the polymerization vessel together with butadiene. The reaction temperature is 90~93 degrees Celsius, and is cooled with liquid ammonia. Diene conversion rate of 80% to 83%, the material residence time in the kettle is about 16 hours. After the reaction, the latex was degassed and defoamed in a degassing tank, and the recovered butadiene was recycled after being compressed and condensed. After the degassed latex is aged for 3 to 4 days, it is sent to storage tanks for ABD use.

Preparation of ABS powder; Add acrylonitrile, styrene monomer and polybutadiene latex to the reaction vessel, using a total of 4 reactors in series, the first three to carry out the reaction, the last is aging. Kettles, all made of stainless steel. The emulsifier is a potassium oleate soap and the trigger is cumyl peroxide. The reaction temperature is 90 degrees and the monomer conversion is 88%. The ABS emulsion from the aging kettle enters two agitated tanks in series for agglomeration. The first tank is used for coagulation and the second tank is used for curing. Agglomeration is dilute sulfuric acid or alum, and the condensation temperature is 90 degrees. After being agglomerated, the ABS fine particles suspended in the mother liquor are washed with a belt filter and sent to dryness. After drying, the water content of the ABS resin can generally be less than 0.5% to 1%, and is sent to the silo for blending with air.

Preparation of SAN resin; Material consisting of styrene monomer, acrylonitrile, solvent ethylbenzene, and recovery liquid is preheated into a polymerizer, acrylonitrile; styrene monomer = 30; 70, ethylbenzene 5 %~10%. The polymerization temperature is 120 to 150 degrees Celsius and the pressure is 0.196 to 0 and 294 MPa. After the reaction, the material from the polymerization tank is sent to the first devolatilizer by a gear pump and flashed at a pressure of 0,196 MPa to remove most of the material. Acrylonitrile and some styrene monomer, ethylbenzene and other volatile components. Then heated to 240 degrees Celsius by the tube heater, enter the second devolatilizer, and remove residual volatile components such as styrene monomer under the pressure of 2.67 kPa. The entire system is insulated with hot oil at 290 degrees Celsius. The melted SAN is sent to the pelletizing pellets and sent to a SAN hopper for blending with the ABS grafted powder.

Blending and granulation; ABS powders are added and mixed with SAN pellets in the mixer and blended using mechanical stirring method. This can very easily adjust the ratio of the three, and greatly enriches the ABS. Resin varieties and grades are wet blended. It then enters a twin-screw extruder and is extruded and pelletized. Finally delivered to the finished ABS silo after packing.

Finally, due to the limitations of the bulk process itself, it is impossible to produce ABS products with rubber content over 20%. The impact strength of the product is limited, and the rubber particle size control is relatively difficult, and it is impossible to achieve emulsion grafting. The high gloss that can be achieved by the SAN blending method has certain limitations in the range and performance of the product, and needs further improvement. Emulsion grafting A bulk SAN blending process involves the following compounding and post-processing of several intermediates. The continuous bulk method is a bulk polymerization in which polybutadiene rubber is directly dissolved in styrene monomer and acrylonitrile. 



blob.png




2018.03.19

Related News

Related Products

  • Holiday Rabbit Home Decoration
  • MgO Standing Snowman Decoration
  • Metal Vase Pitcher For Home And Garden Decoration
  • Metal Haunted House Candle Holder Halloween Set Of 3
  • metal bicycle plant stand boy planter New design
  • metal sea wind chime Glass/Copper Bells/Sea Turtle/crab/sea Horse Garden Home Décor