The heterophase, microemulsion-like polymerization of DMAEMA was carried out in a semibatch process.
A partial, ternary-phase diagram consisting of SDS, water, and DMAEMA is shown in Fig.
In the free-radical crosslinking copolymerization of DMAEMA monomer and BAAm or TEGMA as crosslinking agent using APS--TEMED as a redox-initiator system, the first step occurs between APS and TEMED in which the TEMED molecule is left with an unpaired valance electron.
The experimental results presented here indicate that the hydrogels expand in acidic conditions, because the tertiary amine side groups of DMAEMA chains become protonated in this region and hence, the charge density on the network increases by increasing degree of the protonation.
The pH-sensitive phase-transition phenomenon is associated with the protonation of tertiary amine side groups of DMAEMA chains.
2]-b-PDMAEMA was then obtained by the ATRP of DMAEMA monomers using [(PTMC).
2]-Br was subsequently used as ATRP macroinitiators for the polymerization of DMAEMA.
Figure 4 illustrates the local monomer conversion for 1 - and 2-mm layers of a 70:30 bis-GMA/TEGDMA blend containing 1 wt% CQ in combination with DMAEMA.
4 during polymerization in a 1- and 2-mm thick specimens of a 70:30 bis-GMA/TEGDMA blend containing 1 wt% CQ in combination with DMAEMA.
DMAEMA (phr) NR 1 Pure 0 (a), 5, 15, 30 NR 2 Pure 0 (a), 10, 20 (b), 30 (a) Concentration 0 corresponds to NR with only the initiator.
The experiment NR + 20% DMAEMA was chosen to test this simulation.
Wong Shing has suggested that the grafting of DMAEMA
onto low MW hydrocarbons and homopolymerization occurred through separate mechanisms.