High-temperature degradation of polyacrylic acid in aqueous solution

Abstract

Poly(acrylic acid) (PAA) was decarboxylated in aqueous solution as a function of pH and ionic strength in the temperature range 100–350°C. Degradation kinetics were first order with respect to acid functionality. The rate of decarboxylation at high pH (Eα = 51.1 kcal/mol) was much slower than that at low pH (Eα = 20.3 kcal/mol). At intermediate pH, the reactivity was found to depend on the degree of dissociation of PAA as a functions of ionic strength, pH, and temperature. No monomer was observed in the reaction product. © 1996 John Wiley & Sons, Inc.

Photocatalytic Degradation of Poly(Acrylamide-co-acrylic Acid)

“…The rate of degradation of PAA is doubled at neutral pH, and at basic pH regime, the rate is the lowest for all the polymers. This is consistent with the observation of Gurkaynak et al 20 for the high-temperature degradation of PAA in solution, …”

Influence of inactive electrode components on degradation phenomena in nano-Si electrodes for Li-ion batteries

“…The solids were dispersed in deionized water (the quantity varied depending on the viscosity of the slurry) and mixed by planetary ball milling for 1 h. The resulting slurry was bar-casted on copper foil (Goodfellow, 22 mm thick). After drying at ambient temperature, the electrodes were punched into 20 mm discs and transferred to an Ar-filled glovebox, where they were first dried under vacuum at 80 C for 12 h and then subjected to a final drying step over 6 h at 100 C. The drying temperature was deliberately kept below 125 C in order to avoid condensation reactions of the binder [38,49,50].…”

Oxidative and photooxidative degradation of poly(acrylic acid)

“…Gurkaynal et al determined that the thermal degradation of PAA in aqueous solution in the temperature range 100-350 C takes place by a first order decarboxylation reaction [12]. The MW of PAA determined by GPC did not change significantly during the degradation and PAA solutions contained a waxy precipitate ascertained to be a water insoluble decarboxylated reaction product.…”

“…Pyrolysis of PAA (160-240 C) in a non-oxidative atmosphere results in competitive dehydration and decarboxylation reactions and no acrylic acid formation is observed [11]. Degradation of PAA in water at temperatures 100-350 C resulted in a water insoluble polymer and gel permeation chromatograms indicated absence of monomers in the degradation products [12]. The average molecular weight of the degraded PAA did not change significantly implying loss of carboxylic functionality.…”