Microemulsions viscosity index improvers

The polymerization of Cg-ia alkyl acrylates and methacrylates in microemulsion media produced translucent and stable latexes with final particle sizes in the range 30-70 mn. The molecular weights of the microemulsion products were found to be higher than those of the emulsion products synthesized under similar conditions. The microemulsion products were also more effective as viscosity index improvers in the paraffin base oil SN 500 than the emulsion products. 

The more branched polymers are supposed to offer more resistance to the flow of oil. From Table 8 it can be noted that poly(2-ethyl hexyl methacrylate) was more effective in viscosity enhancement than its linear counterpart polyCoctyl methacrylate). From Table 8 it is clear that for any additive [except polyCdodecyl acrylate)] synthesized in our laboratory in a microemulsion medium the g > 1, which indicates that additives improve the viscosity index because the thickening effect is greater at 100°C than at 40°C. However, poly(dodecyl methacrylate) was found to be the most effective additive as its Q value 1, indicating that its thickening effect is the same at both high and low temperatures. 

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