Study on the Reaction of Acetylated Konjac Glucomannan and EVA during Processing

2011 ◽  
Vol 695 ◽  
pp. 61-64 ◽  
Author(s):  
Xian Hong Li ◽  
Xiao Yan Lin ◽  
Xue Gang Luo ◽  
Ji Wei Li
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Vinyl Acetate ◽  
Ethylene Vinyl Acetate ◽  
Konjac Glucomannan ◽  
Ft Ir

The transesterification in acetylated konjac glucomannan/ethylene vinyl acetate (AKGM/EVA) melting blend system with the presence of dibutyltin oxide (DBTO) catalyst was investigated by means of a torque rheometer during compounding. The characteristics of the products were evaluated by DSC and FT-IR. The glass transition temperature at about 179.4 °C was found in the DSC curve of AKGM-EVA, the equilibrium torque of AKGM/EVA with 0.25 wt% DBTO was lower than that without DBTO. The results showed that the transesterification took place in the AKGM/EVA blend system.

scholarly journals Melt Stable Functionalized Organosolv and Kraft Lignin Thermoplastic

Processes ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1108
Author(s):  
Shubhankar Bhattacharyya ◽  
Leonidas Matsakas ◽  
Ulrika Rova ◽  
Paul Christakopoulos
Keyword(s):  
Thermal Stability ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Kraft Lignin ◽  
Added Value ◽  
Lignin Valorization ◽  
1H Nuclear Magnetic Resonance ◽  
Ft Ir ◽  
Viable Biomass

A shift towards an economically viable biomass biorefinery concept requires the use of all biomass fractions (cellulose, hemicellulose, and lignin) for the production of high added-value products. As lignin is often underutilized, the establishment of lignin valorization routes is highly important. In-house produced organosolv as well as commercial Kraft lignin were used in this study. The aim of the current work was to make a comparative study of thermoplastic biomaterials from two different types of lignins. Native lignins were alkylate with two different alkyl iodides to produce ether-functionalized lignins. Successful etherification was verified by FT-IR spectroscopy, changes in the molecular weight of lignin, as well as 13C and 1H Nuclear Magnetic Resonance (NMR). The thermal stability of etherified lignin samples was considerably improved with the T2% of organosolv to increase from 143 °C to up to 213 °C and of Kraft lignin from 133 °C to up to 168 °C, and glass transition temperature was observed. The present study shows that etherification of both organosolv and Kraft lignin with alkyl halides can produce lignin thermoplastic biomaterials with low glass transition temperature. The length of the alkyl chain affects thermal stability as well as other thermal properties.

Influence of PCBM on the Glass Transition Temperature (Tg) of Poly(N-Vinylcarbazole)-Based Photorefractive Composite

2017 ◽  
Vol 896 ◽  
pp. 62-71 ◽  
Author(s):  
Bai Li Chen ◽  
Chuan Qun Huang ◽  
Rui Zhuang Yang ◽  
Yu Fang ◽  
Qing Jun Zhang ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Acid Methyl Ester ◽  
Differential Scanning Calorimetric ◽  
H Nmr ◽  
Composite Polymers ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Dsc Method

2,5-dimethyl-(4-p-nitrophenylazo) phenetole (DMNPAPE) was synthesized. And its structure was confirmed with ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared (FT-IR) spectra and 1H Nuclear Magnetic Resonance (1H NMR) spectroscopy. The photorefractive composite consist of 33 wt % poly (N-vinycarbazole) (PVK), 50 wt % 2, 5-dimethyl-(4-p-nitrophenylazo) phenetole (DMNPAPE) and 16 wt % ethyl carbazole (ECZ) doped with x wt % (≤1 wt%) [6, 6]-phenyl C61 butyric acid methyl ester (PCBM) was fabricated. The influence of PCBM on the glass transition temperature (Tg) of the photorefractive composite was studied using a differential scanning calorimetric (DSC) method. The active energy of glass transition (Eg) was evaluated by Kissinger’s and Moynihan’s relation. The analysis results indicate that the transition region shifts to higher temperatures with the increasing heating rate, and PCBM content (≤1.0 wt %) can influence Tg of PVK - based PR composite polymers. The Tg first increase and then went down with the PCBM content (below 1.0 wt %) increasing. The possible cause of the influence of PCBM on Tg was proposed.

scholarly journals Self-Plasticization of PVC via click reaction of a monooctyl phthalate derivative

2017 ◽  
Vol 19 (3) ◽  
pp. 16-19 ◽  
Author(s):  
Puyou Jia ◽  
Rui Wang ◽  
Lihong Hu ◽  
Meng Zhang ◽  
Yonghong Zhou
Keyword(s):  
Thermal Stability ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Click Reaction ◽  
Element Analysis ◽  
Migration Resistance ◽  
Ft Ir ◽  
And Migration ◽  
High Migration

Abstract Modified PVC (M-PVC) material with suppressed migration and low glass transition temperature was prepared via click reaction of a monooctyl phthalate derivative. Chemical structure and composition of M-PVC were characterized by FT-IR, 1H NMR and element analysis. Thermal stability, glass transition temperature and migration stability of M-PVC were studied with TGA, DSC and migration tests, respectively. The study showed that M-PVC exhibited poor thermal stability, and low glass transition temperature of 66.0°C. No migration was found in distilled water, 10% (v/v) ethanol, 30% (w/v)acetic acid and petroleum ether. The PVC material is expected to preparing PVC products in the areas with high migration resistance requirement.

Novel Applications of the QCM Technique in Biomaterials Science

2007 ◽  
Vol 1060 ◽  
Author(s):  
Candida Costa Silva ◽  
David C Lin ◽  
Iren Horkayne-Szakaly ◽  
Peter J Basser ◽  
Ferenc Horkay
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Vinyl Acetate ◽  
Reasonable Agreement ◽  
Quartz Crystal ◽  
Vapor Sorption ◽  
Different Temperatures ◽  
Novel Applications ◽  
Quartz Sensor

ABSTRACTA quartz crystal microbalance (QCM) has been used to investigate polymer samples. The vapor sorption of three different polymer samples (poly(vinyl acetate), polybutadiene and polydimethylsiloxane) was studied. The change in resonance frequency of the quartz sensor uniformly coated with polymer films was measured as a function of the film thickness and water absorption at different temperatures. The range of linear frequency vs. mass response was determined in the absence of absorbed water. The glass transition temperature of thin poly(vinyl acetate) films (10 nm <thickness< 1000 nm) was found to be in reasonable agreement with published values for macroscopic samples.

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