Methods

The following production procedures were used to polymerise acrylamide using oil soluble and water soluble initiator: With water soluble redox initiators, the following procedure was used:

1. Purge aqueous phase and oil phase separately with nitrogen for 20 minutes;
2. Add the oil phase to mixing beaker of the Silverson mixer;
3. Start the mixer and add aqueous phase slowly to the oil phase in the mixing beaker under continuous nitrogen purging;
4. Stir for 4 minutes at maximum speed;
5. Transfer the pre-emulsion into the reaction vessel and purge for 20 minutes with nitrogen whilst stirring at 250 rpm (ca 4 Hz); maintain the temperature of the water bath at 50±° C.;
6. at a reaction temperature of 45±1° C. and after increasing the stirrer speed to 800 rpm (ca 13 Hz), start the initiator feed; 10 ml of 0.15% Na2S2O5 in demineralised water for 500g emulsion added during period of 4 hours;
7. After addition of initiator, feed mop-up to the emulsion 4 ml of 15.0% Na2S2O5 in demineralised water for 500 g emulsion, added over period of about 30 minutes; After completion of the polymerisation, the emulsion was filtered and the residue on the filter was measured. Polymerisation with dissociative, oil soluble initiator (AIBN) Similar procedure to except that in step 6-7:
8. Add all initiator (1 ml of 1 part AIBN in 5 parts acetone for 500 g emulsion) at once when the temperature of the pre-emulsion reaches 40±1° C.
9. Polymerise for 6 hours whilst purging with nitrogen

미국특허 US 6686417 B1
Surfactant composition for inverse emulsion polymerization of polyacrylamide and process of using the same

특허를 통한 기술 이해

Water-in-oil polymer emulsions, process for their preparation and their use  / EP 0623630 A2

바스프의 이 기술은 상기의 수용성 촉매를 사용하는 방법보다 쉬운것 같다. Free radical - 유용성 촉매(AIBN)를 사용하고 있고 온도 컨트롤만하면 적용이 쉬운편이다. 특이한 사항은 사용하는 계면활성제중 하나를 고분자 타입을 사용하고 있다. 아마도 AIBN의 용이한 분배를 목적으로 적용하는 것으로 보인다. 하이퍼머 시리즈는 다양한 고분자형 계면활성제를 제공하므로 적용하려는 연속상과  선택한 유용성 촉매의 성질을 고려하여 선택하면 될 것같고.......

사용하는 개시제(initiator)는 대부분의 특허에서 AIBN(VAZO 64)를 이용하고 있다. 좀 더 낮은 온도에서 개시반응을 유도하려면 VAZO 52를 개시제 총량대비 10정도 혼용하면 된다.

In a 2-liter flask provided with a stirrer, a thermometer and a gas inlet tube, Priority

• 270 g of rapeseed oil
• 30 g emulsifier 1
• 30 g of sorbitan monooleate
• 380 g of 50% aqueous acrylamide solution
• 0.1 g of 40% aqueous solution of diethylenetriaminepentaacetic acid sodium

and the mixture is stirred at a speed of 200 rpm while introducing nitrogen for 30 min. at a temperature of 25 ° C. Then add 0.1 g of dimethyl 2,2'-azobisisobutyrate in 1 g of acetone added and the reaction mixture heated to 55 ° C.

During the polymerization, the bath temperature is controlled so that the temperature of the reaction mixture remains constant. After completion of the polymerization, 0.07% coagulum were filtered off. The polymer had a K value of 240, the viscosity of the emulsion was 1300 mPas.

As component (a) of the emulsifier used is a polyester-polyethylene oxide-polyester block copolymer having a molecular weight of> 1000 g / mol, which is prepared by reacting condensed 12-hydroxystearic acid with polyethylene oxide according to the teaching of EP-A-0000424 and is commercially marketed under the name Hypermer B246. This emulsifier is hereinafter referred to as emulsifier 1.

하미퍼머 상품 자료  

UNIQEMA-HypermerPolymericSurfactants.pdf