Degradation of Acrylic Acid-Grafted Cellulose in Aqueous Medium With Radical Initiators

Abstract

The chemical modification of cellulose by grafting reaction with Acrylic Acid (AA) considering different reaction factors was investigated. Natural polymers such as Santa Fe Cellulose, Microcrystalline Cellulose (Avicell) and Secondary Pulp were studied as substrates. pH effect; Ce (IV), Mn(VII) and Fenton as initiators; time and temperature polymerization were investigated. Grafting reachs a maximum, 90 % graft, at pH 7. A medium to weak C=O band at 1715 cm -1 for carboxylic group in FTIR spectroscopy is presented. Santa Fe and Avicel cellulose grafted whith AA at 17 hours are degraded. Secondary pulp with Fenton at 50-60 and 70 ºC at 17 hours are degraded too. The degradation of polymers at long reaction times at 17 hours and 70ºC were analized by FTIR spectroscopy and electronic microscopy analysis (SEM).

Improving the Compatibility of Zein/Poly(vinyl alcohol) Blends by Gamma Irradiation and Graft Copolymerization of Acrylic Acid

“…The decrease of the O−H band, associated with a broader shape and a shift toward lower frequencies, could be due to a stronger hydrogen bonding level between the various groups formed during the grafting process. Moreover, a new band appeared at 3000−3100 cm −1 and is assigned to unsaturated methylene CH stretching from AAc in the polymer blend, as described by ref . Furthermore, a broad symmetric CO stretching band also appeared clearly at ∼1730 cm −1 , as compared to ungrafted blends, hence suggesting the presence of AAc (or PAAc) interactions within the zein/PVA blend.…”