Thermal Degradation of Polyurethane Bicomponent Systems in Controlled Atmospheres

Abstract

Although the thermal degradation of polyurethanes has been extensively studied in the past, the use of a panoply of recent analytical techniques has provided more detailed data and enabled us to confirm prior findings on the thermal degradation of bicomponent polyurethanes. The thermal behaviour of bicomponent polyurethanes in conditions of controlled atmosphere and temperature was characterized by determining their heat stability by on-line TGA/FT-IR coupling and off-line TGA/TCT/GC/MS coupling in order to identify the volatile compounds released. Degradation residues were analyzed by FT-IR and MALDI-TOF (matrix assisted laser desorption/ionization coupled with time-of-flight) mass spectrometry. A major drawback of these thermoplastic elastomers is that one of the components, isocyanate, is toxic. Based on the data obtained with model urethane compounds ( p-TI-based) and bicomponent polyurethane polymer (MDI- and PEG-based), we show that the thermal degradations are different. The widespread application of these materials exposes them to extreme working conditions, which is why we propose reaction mechanisms for their degradation.

Polyurethanes from benzene polyols synthesized from vegetable oils: Dependence of physical properties on structure

“…It is known that vegetable oil based PUs start their degradation by dissociation into polyols and precursors of urethanes 7. The release of CO 2 gas was associated to the dissociation of urethane linkage into primary amine and olefin 37. Similarly to their corresponding monomers, the degradation of the dangling chains started at 365°C for both matrices.…”

Mechanically strong and resilient shape memory polyurethane with hexamethylene diisocyanate as mixing segment

“…Figure 4 illustrates the TGA thermogram of prepared SMPU film. The thermal degradation of shape memory polyurethane occurs in a two-step process (Ketata et al, 2005). The TGA studies indicate the mass loss due to urethane link breakage from 285°C ( T i ) to 456°C (T s ).…”

Preparation and Characterization of GF Modified Waste Rigid Polyurethane Foam

“…In the preparation process of polyurethane rigid foam materials, chain extension, gas generation and cross-linking branching reactions are first carried out [20,21]. After the reaction of the polyurethane, that the diethylene glycol acts as an alcoholysis agent is contributes to forming a special-purpose polyurethane foam with some degree density, cross-linking degree and mechanical properties.…”