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JSIR Vol.63 [2004] >
JSIR Vol.63(07) [July 2004] >
| Title: | Studies on the properties of carboxymethylated polyvinyl alcohol |
| Authors: | Mukherjee, G S
Shukla, N
Singh, R K
Mathur, G N |
| Keywords: | Polyvinyl alcohol
Carboxymethylation
Thermal analysis
Mechanical strength |
| Issue Date: | Jul-2004 |
| Publisher: | CSIR |
| IPC Code: | Int. Cl.7: G 01 N 23/207, G 01 N 25/02 |
| Abstract: | Polyvinyl alcohol (PVA) has been chemically modified to its carboxymethylated form and the product, designated as CPVA are cast into transparent films. It was observed that the mechanical strength of CPVA film was much higher than that of PVA. The wide angle X-ray diffraction (WAXD) pattern showed a higher molecular order in CPVA compared to that in PVA. Influence of water towards CPVA was found to be quite different as revealed from the studies based on DSC, FTIR, WAXD and mechanical strength evaluation. Because of higher molecular order, water sorption of CPVA membrane was found to be lower than that of PVA. The interplaner distance for PVA was found to be higher than that of CPVA. Interestingly, DSC profile of PVA and CPVA showed different features; PVA underwent an exothermic change at a peak exothermic temperature of Tp=76.7o followed by two distinct endothermic changes. Interestingly, CPVA neither showed any such initial exothermic nor any initial endothermic change unlike showed by PVA but it did exhibit only one distinct endothermic change at trough melting temperature of Tt2=207.3o. The value of entropy of melting for PVA and CPVA corroborates with their respective WAXD pattern. |
| Page(s): | 596-602 |
| ISSN: | 0975-1084 (Online); 0022-4456 (Print) |
| Source: | JSIR Vol.63(07) [July 2004]
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