Fourier transform infrared spectroscopy (FT-IR) is employed for the quantitative tracking of the structural evolution of poly(acrylonitrile-co-itaconic acid) (PAI) with different itaconic acid (IA) contents during its thermal oxidative stabilization (TOS). The TOS process includes cyclization, oxidation and tautomerization, as characterized by the evolution of the overlapping peaks of cyclic CC, CN, N–H and CO vibrations in FT-IR. The second derivatives of the spectra facilitate the identification of the position of each contributing structure. The following peak-fitting operations and the determination of the molar absorption coefficients using model compounds allow the quantitative tracking of the extent of the TOS process. PAI containing approximately 3 mol % IA exhibits the most efficient TOS process in terms of cyclization, oxygen uptake and dehydrogenation reactions. A quantitative investigation of the evolution of PAI using FT-IR is an efficient way to determine the optimal structural characteristics of the precursors for carbon materials.

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This study reports the influence of nano‐silica particles (0.0–0.45 %wt) on properties of polyurethane foams (PUF) using monoglycerides, sorbitol, and glycerol as components of polyol. The morphology, density, mechanical, thermal stability, and thermal conductivity properties of samples were investigated in this study. When 0.35 %Wt of nano‐silica was used to reinforce PUF, the compression strength of PUF achieved the highest value (82.49 kPa). The thermal gravimetric analysis showed that the presence of nano‐silica can improve the thermal stability of PUF samples. Scanning electron microscopy studies indicated that PUF samples containing 0.3, 0.35, and 0.45 %Wt of nano‐silica had more uniform cell structures than pure PUF sample. Finally, the thermal conductivity of pure PUF and PUF/nano‐silica were measured at three different levels of humidity (33% RH, 57% RH and 75% RH) at 25°C. The lowest thermal conductivity value achieved was 0.034 W/mK.

Montmorillonite (MMT) of which the surface was modified with a block copolymer with crosslinkable units was incorporated into methacrylate‐based composites as nanofiller to improve dimensional and mechanical properties. A bifunctional block copolymer containing 2‐isocyanato ethyl methacrylate in one block and poly(vinyl pyridine) units in the other block was prepared as the block copolymeric surface modifier for MMT through controlled/“living” radical polymerization technique. Application of the modified MMT in 2,2‐bis[4‐(2‐hydroxy‐3‐methacryloyl‐oxy)phenyl]propane (bis‐GMA) based composites showed that polymerization shrinkages of the composites decreased as the content of modified MMT increased. Compressive and flexural strengths of the composites were also improved in the presence of the modified MMT, which demonstrate the beneficial effect of the modified MMT as a nanofiller and IEM as a cocrosslinkable unit. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013