BIODEGRADATION OF PHENOL-FORMALDEHYDE RESINS MODIFIED WITH COMMERCIAL LIGNINS

M. BERNARD; V. NICOLAU; M. SPONTÓN; D. ESTENOZ

Cuiabá

Congreso; 21 Congreso de Ingeniería y Ciencias de los Materiales CBECIMAT 2014; 2014

This work aims to study the biodegradation of partially modified resols with 10% w/w of sodium lignosulfonate and 10 and 20 % w/w of Kraft lignin type, respectively; using a traditional resin as a witness. The experimental work involved preliminary studies of biodegradation in Petri dish (clear zones), the degradation of resols by enzymatic attack of Pseudomonas aeruginosa under aerobic conditions for a period of 200 days and the spectroscopic (FT-IR, RMN), chromatographic (GC) and morphological (SEM) characterization of the polymers before and after biodegradation. The number of viable cells showed a significant increase during the process. However, the gravimetric analysis was not sufficient to check the biodegradation. The results indicated that endocellular enzymes could be involved. It was observed that the presence of low concentrations of toxic substances released during degradation of the material may have inhibitory effects. Resoles were synthesized in Centro S.A., San Francisco , Córdoba.