carried out because the maximal solubility of acrylamide in acetone
is only 20 wt% at room temperature. It is suggested that monomer
concentration controls the diffusion of monomer, the higher is the
monomer concentration, the more polymerization chains can be
formed. The effect of irradiation time on photopolymerization and
surface photografting has also been examined and the results are
presented in Fig. 3. The used monomer concentration is 20%. It can
be seen that P% is 3.8% and DP is zero when irradiation time is less
than 1 min, indicating that no involvement of photografting reaction
during this period. P% reaches its maximal value with the
irradiation time of 30 min. DP values and Eg of acylamide increase
with the increase of irradiation time before 40min. The longer the
irradiation time is, the more is the DP value. This may suggest some
homopolymer chains have attached on the surface of fabric
samples by coupling reaction [22]. DP reaches its maximum value
of 32.5% when irradiation time is 40 min. The increasing trend stops
when irradiation time reaches 40 min, which maybe due to the
consumption of initiator and monomers and the increasing
coverage of the polymer surface by grafting chains [23].