Kinetics and mechanisms of flash pyrolysis of poly(methyl methacrylate) (PMMA)

Journal Article · Thu May 01 04:00:00 EDT 1997 · Combustion and Flame

DOI:https://doi.org/10.1016/S0010-2180(96)00190-3· OSTI ID:543413

Arisawa, H; Brill, T B ^[1]

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1. Univ. of Delaware, Newark, DE (United States). Dept. of Chemistry

Flash pyrolysis (600--1,000 C/s) of a film of anionically polymerized poly(methyl methacrylate) (PMMA) was conducted at controlled temperatures in the 380--600 C range by T-jump/FTIR spectroscopy. In the endothermic decomposition process, the methyl methacrylate monomer (MMA {ge} 90%) and CO{sub 2} ({le} 10%) are the only pyrolysis products detected. Arrhenius parameters for evolution of MMA and CO{sub 2} were determined under a pressure of 2 and 11 atm Ar for PMMA with MW = 2,000 and 131,000. A zeroth-order rate model was used. A slope break occurs at 460--500 C in the Arrhenius plots. Below this range for MMA, E{sub a} = 43--66 kcal/mol and In(A/s) = 26--44, which are comparable to previous reports for random C-C scission kinetics. For CO{sub 2}, E{sub a} = 39--46 kcal/mol and In(A/s) = 23--27, which are comparable to the decarboxylation rates of other organic compounds. Above 460--500 C, increased control of the rates by desorption/diffusion of MMA and CO{sub 2} is suggested by the lower values of E{sub a} in the 12--30 kcal/mol range and In(A/s) in the 5.7--17 range. Thus, the limiting temperature of pyrolysis of PMMA is about 500 C before the deconsolidation rate of the pyrolysis products begins to take control from the bulk decomposition rate in determining the rate of product evolution.

• OSTI ID: 543413
• Journal Information: Combustion and Flame, Journal Name: Combustion and Flame Journal Issue: 3 Vol. 109; ISSN 0010-2180; ISSN CBFMAO
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
ACTIVATION ENERGY
CHEMICAL REACTION KINETICS
FLASH HEATING
INCINERATORS
MATHEMATICAL MODELS
MUNICIPAL WASTES
PMMA
PYROLYSIS
PYROLYSIS PRODUCTS