Water Soluble Thermosetting Acrylic Resins for Industrial Paints (I)

Study on Monomer Composition of Four-Components Copolymer

Abstract

The monomer mixture containing styrene (St) 19. 2 mole%, butyl acrylate (BA) 56.0 mole%, itaconic acid (IA) 11.0 mole% and β-hydroxyethyl methacrylate (HEMA) 13.8 mole% was copolymerized by means of batch type free radical polymerization system where all the monomers were included in the initial charge. The four-components copolymer compositions in various conversion rate were measured by means of NMR spectra, and compared with the values calculated from Alfrey-Price Q and e scheme using a digital computer.
(1) The accumulated copolymer composition analyzed by NMR spectra in low conversion rate (33%) was as follows.
St : BA : IA : HEMA=35 : 37 : 6 : 22 mole%
St content was about two times higher than the initial content, but BA content was lower.
(2) St content of the accumulated copolymer decreased continuously, while BA content increased with increase of the conversion rate.
(3) IA and HEMA contents were very close to the initial contents in all conversion levels. It is a very useful distribution characteristic for the thermosetting coating resin.
(4) Above results coincided very well with the results calculated from Alfrey-Price Q and e scheme.