Translucent nanolatexes through emulsion polymerisation of ethyl acrylate

Turbid emulsion systems of ethylacrylate/sodium dodecyl sulphate/water with monomer to surfactant (M/S) ratios 10 and 40 were transformed into stable transparent/translucent nanolatexes through emulsion polymerisation using potassium persulphate as an initiator. The latex particle size was observed to be similar to that obtained by true microemulsion polymerisation where M/S ratio is one. The kinetic plots exhibited two intervals upto M/S ratios 10. AIBN initiated systems showed separation of two phases for the M/S ratio greater than or equal to 10. M/S ratios were varied from 1 to 54 for the comparative Study of polymerisation in emulsion and microemulsion media. Gel effect dominance was observed around 40-60% conversion for the microemulsion polymerisation of ethylacrylate. Only one chain per particle was observed for microemulsion system with M/S ratio 1 and three to four chains per particle were observed for the systems with M/S ratios 10 and 40. Unlike M/S = 1 system. higher dependency of polymerisation rate on initiator concentration was observed for the systems with M/S = 10 and 40. A possible mechanism for such a transformation has been proposed. (C) 2002 Elsevier Science Ltd. All rights reserved.