Gelatin‐based composite polymers

Composite polymers containing gelatin and polymethyl methacrylate (PMMA) have been prepared by employing a gel pathway. The gels have been obtained by mixing mechanically at 50°C an aqueous solution of gelation containing a surfactant (sodium dodecylsulphate, SDS) with a monomer (methyl methacrylate, MMA) containing an initiator (AIBN). Two kinds of gels have been identified: high‐viscosity liquid gels, which lose their stability after half to two hours at room temperature, and solid‐type gels, which maintain their stability for a long time at room temperature. Composite polymer materials have been obtained by the polymerization of MMA in these gels. The polymerization of liquid‐type gels has been carried out in two steps: under mixing for the first hour and without mixing for 23 h. The polymerization of the solid‐type gels was performed in two different ways: (1) at room temperature for a few days followed by heating at 50°C for 4 h, and (2) the same procedure as for the liquid‐type gels (since at 50°C the solid‐type gels transform in liquid‐type gels).The phase behavior of the gels was investigated and scanning electron microscopy (SEM) was used to examine the morphology of the composite polymers. The swelling experiments have shown that at suitable gelatin concentrations, these composites are insoluble in water, methanol, octane, and cyclohexane but have a relatively high solubility in toluene.