Surface photografting
Free radicals on the nylon-6,6 chain can be formed by hydrogen
abstracting reaction in the presence of benzophenone as a photoinitiator.
It is suggested that monomers firstly react with these free
radicals and then the polymerization propagate from grafting
points to form grafting chains on nylon-6,6 fabric surface
(Scheme 1) [20e22]. The effects of monomer concentration and
irradiation time on degree of photopolymerization (P%), degree of
surface photografting (DP) and grafting efficiency (Eg) were investigated
respectively. The effect of monomer concentration on
photopolymerization and photografting is shown in Fig. 2. The used
irradiation time is 40 min. It can be observed that P%, DP and Eg
increase with the acrylamide concentration. DP can reach up to
31.3% when acrylamide concentration is 20%. And both P% and Eg
reach the maximum values at this monomer concentration.