Facile access to poly(NMA-co-VCL) hydrogels via long range laser ignited frontal polymerization

We report a new method for the facile and fast synthesis of poly(NMA-co-VCL) (NMA = N-methylolacrylamide, VCL = N-vinylcaprolactam) hydrogels via infrared laser ignited frontal polymerization (LIFP). Once LIFP was initiated, no further energy was required for the following polymerization. We investigated the dependence of the frontal velocity and temperature of the LIFP on the NMA:VCL weight ratio in detail, as well as the swelling behavior and morphology properties of the as-prepared hydrogels. The swelling capacity of the hydrogels prepared by LIFP was superior to that obtained by the traditional thermal frontal polymerization (TFP) method. More interestingly, LIFP could be successfully carried out using a long range infrared laser inducer with remote control. With a further increase in the infrared laser energy, longer range LIFP could be also achieved, making it possible to deal with spilled toxic substances without being close to the location of the reaction.