Crosslinking of poly(vinyl alcohol) using dianhydrides as hardeners

Abstract

SYNOPSISThe crosslinking reaction of poly(viny1 alcohol) (PVA) with 3,3',4,4'-tetracarboxybenzophenone dianhydride, pyromellitic carboxylic acid anhydride, and Epiclon B-4400 as hardeners was studied either in solution or by differential scanning calorimetry. A catalyst agent had to be used in all cases. Depending on the concentration of hardener and catalyst, differences are observed. TB values increase with the ratio of hardener and catalyst, while activation energies decrease with the amount of catalyst but little changes can be seen when different dianhydride amounts are used. The thermal properties of the final products were unaltered by the hardener used. The decomposition temperature is initiated at a similar temperature in linear and crosslinked PVA, but while uncured PVA undergoes a complete degradation in one step, crosslinked PVA degrades in several steps. 0 1996 John

Polyvinyl alcohol as the barrier layer in thin film composite nanofiltration membranes: Preparation, characterization, and performance evaluation

“…Hence there is a need to balance the hydrophilic and hydrophobic properties of such membranes, which may be achieved by cross-linking [14,15]. PVA may be cross-linked by using multifunctional compounds, such as dialdehydes [16][17][18], dicarboxylic acids [19,20], and dianhydrides [21], which are capable of reacting with the hydroxyl groups of PVA. Cross-linking improves the stability of such membranes.…”

Poly(vinyl alcohol) Rehydratable Photonic Crystal Sensor Materials

“…PVAPCCA Hydrogel Carboxylation: The PVAPCCA was carboxylated by treatment with succinic anhydride in an anhydrous solvent, such as DMSO, (Figure 8) [37]. This was accomplished by first transferring the PVAPCCA to DMSO and allowing it to equilibrate.…”

“…[27][28][29][30][31] However, due to the cytotoxic nature of glutaradehyde [32][33][34][35] several groups have prepared chemically crosslinked PVA hydrogels utilizing other crosslinkers such as epichlorohydrin, [36] diglycidyls, [37] or by incorporation of polymerizeable functionalities [38][39][40][41][42][43] onto the PVA backbone.…”

Synthesis and characterization of PVA/PES thin film composite nanofiltration membrane modified with TiO2 nanoparticles for better performance and surface properties

“…Hence there is a need to balance the hydrophilic and hydrophobic properties of such membranes, which might be achieved by cross-linking [23,24]. PVA can be cross-linked by using multifunctional compounds, such as dialdehydes [25][26][27], dicarboxylic acids [28,29], and dianhydrides [30], which are capable of reacting with the PVA hydroxyl groups. Cross-linking improves the stability of such membranes.…”