Influence of hydrogen bonding interaction on the damping properties of poly( n- butyl methacrylate)/ small molecule hybrids

The hydrogen bonding interactions between poly(n-butyl methacrylate) and a series of low molecular weight phenols containing two to four hydroxyl groups with different steric effects were investigated by differential scanning calorimetry and Fourier-transform infrared spectroscopy. Results showed that the hydrogen bonding strength between the two components varies greatly according to the steric effects of the phenolic hydroxyl group. As the size of the group beside the hydroxyl increases, the hydrogen bond strength weakens. The glass transition temperature of binary hybrid systems was put into relation with the corresponding hydrogen bonding interaction strength. Strong hydrogen bonding strength increased T-g to higher values than that predicted by the linear additivity rule; by contrast, T-g of hybrid systems with weak hydrogen bonds showed linear changes. All of the samples showed linear variations at low concentrations of small molecules. The damping properties of five systems were analyzed by dynamic mechanical analysis. Either the loss factor or area of tan peak of the five systems increased compared with that of the pure polymer, thereby showing great improvements in the damping properties of the poly(n-butyl methacrylate)/small molecule hybrid material. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41954.