Synthesis and Thermal Properties of Acrylonitrile/Butyl Acrylate/Fumaronitrile and Acrylonitrile/Ethyl Hexyl Acrylate/Fumaronitrile Terpolymers as a Potential Precursor for Carbon Fiber

Abstract

A synthesis of acrylonitrile (AN)/butyl acrylate (BA)/fumaronitrile (FN) and AN/EHA (ethyl hexyl acrylate)/FN terpolymers was carried out by redox polymerization using sodium bisulfite (SBS) and potassium persulphate (KPS) as initiator at 40 °C. The effect of comonomers, BA and EHA and termonomer, FN on the glass transition temperature (T g ) and stabilization temperature was studied using Differential Scanning Calorimetry (DSC). The degradation behavior and char yield were obtained by Thermogravimetric Analysis. The conversions of AN, comonomers (BA and EHA) and FN were 55%-71%, 85%-91% and 76%-79%, respectively. It was found that with the same comonomer feed (10%), the T g of AN/EHA copolymer was lower at 63 °C compared to AN/BA copolymer (70 °C). AN/EHA/FN terpolymer also exhibited a lower T g at 63 °C when compared to that of the AN/BA/FN terpolymer (67 °C). By incorporating BA and EHA into a PAN system, the char yield was reduced to ~38.0% compared to that of AN (~47.7%). It was found that FN reduced the initial cyclization temperature of AN/BA/FN and AN/EHA/FN terpolymers to 228 and 221 °C, respectively, in comparison to that of AN/BA and AN/EHA copolymers (~260 °C). In addition, FN reduced the heat liberation per unit time during the stabilization process that consequently reduced the emission of OPEN ACCESSMaterials 2014, 7 6208 volatile group during this process. As a result, the char yields of AN/BA/FN and AN/EHA/FN terpolymers are higher at ~45.1% and ~43.9%, respectively, as compared to those of AN/BA copolymer (37.1%) and AN/EHA copolymer (38.0%).

Improved Method for Preparation of Amidoxime Modified Poly(acrylonitrile-co-acrylic acid): Characterizations and Adsorption Case Study

“…As shown in Figure 7b (in the range of 400-900 °C) PAN has a more intense peak compared to poly(AN-co-AA). Similar observations were reported while comparing degradation peak of PAN with poly(acrylonitrile-fumaronitrile) [2,13]. The most broad with less intense peak in the DTG curve is poly(AN-co-AA) 93:7 indicating that the degradation occurred at slower rate.…”

“…PAN has the highest yield (73% ± 0.5%) due to the non-incorporation of comonomer that may interrupt the polymerization reaction [2,13]. However, the yield percentage of poly(AN-co-AA) 97:3 is lower at 64% ± 1.4%.…”

“…under mild condition [2,13]. The modification of poly(AN-co-AA) with hydroxylamine hydrochloride involved less chemical consumption with a short reaction time.…”

Purification and Characterization Methods for Lignin Biomass as a Potential Precursor for Carbon Materials

“…Compounds like cellulose products are referred to as contaminants. 34,35 Figure 10: Structures of lignin and cellulose biomass analysed by 13 C NMR (S corresponds to syringyl lignin and G corresponds to guaiacyl lignin) 41 Table 9 Signal assignments for 13 C NMR of kraft lignin and sugarcane lignin 33,39 Chemical shift (ppm)…”

Evaluation of Acrylonitrile/Butyl Methacrylate/Halloysite Nanoclay Impregnated Wood Polymer Nanocomposites

“…Figure 9 shows that the AN-co-BMA-HNC WPNCs had a higher weight percent loss compared with the RW. This was due to the effect of the acrylate group, which interrupted the nitrile sequence along the acrylonitrile and aided in forming a new chemical bond with butyl methacrylate and halloysite nanoclay (Jamil et al 2014). This bond was linked together in the impregnated wood fiber to enhance the chain mobility of the WPNCs and thus improved the thermal stability of the WPNCs.…”