Abstract
An emulsifier-free emulsion was synthesized via the preemulsified emulsion polymerization, with styrene (St), butyl acrylate(BA), and ammonium allyloxtmethylate nonylphenol ethoxylates sulfate (DNS-86) as the polymerizable emulsifier. The influences of the reaction temperature and time, DNS-86 amount on the emulsion polymerization were investigated, then the most suitable polymerizing conditions were obtained, the semi-continuous method was used, T=80°, t = 5 h, the dosage of DNS-86 was 2% of total monomers mass. The analysis of the profiles of IR, NMR, and Laser particle size demonstrated that the copolymerization occurred between St, BA and DNS-86 to generate P(St-BA-DNS-86) successfully, and hydrophilic sulfonic groups containing the copolymer were conducive to emulsion stability. Besides, the influences of the dosages of DNS-86 on the latex solid content and average particle size were discussed. The result showed that with the increase of DNS-86 amount, the latex solid content increased and average particle size of latex reduced, e.g., at the 2% mass amount of DNS-86 52.50% of the latex solid content, 78 nm of average diameter, 0.0379 of particle size distribution. Latex of high solids of up to 62.1% has been obtained with 5% DNS-86. The results of TEM showed that the copolymer emulsion with smaller particle size and uniform distribution could be obtained by using polymerizable emulsifier DNS-86.