Thermal degradation studies of polyurethane/POSS nanohybrid elastomers

• Published in: Polymer degradation and stability Vol. 95; no. 6; pp. 1099 - 1105
• Main Authors: Lewicki, James P., Pielichowski, Krzysztof, De La Croix, Pauline Tremblot, Janowski, Bartlomiej, Todd, Deborah, Liggat, John J.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.06.2010; Elsevier
• Subjects: Applied sciences; BUTANE; CHAINS; Chemical modifications; Degradation; DISTRIBUTION; Elastomer; ELASTOMERS; EVAPORATION; Exact sciences and technology; HYBRID SYSTEMS; Inorganic and organomineral polymers; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; Nanomaterials; Nanostructure; Physicochemistry of polymers; Polyurethane; Polyurethane resins; POSS; STABILITY; SYNTHESIS; THERMAL DEGRADATION; THERMAL GRAVIMETRIC ANALYSIS; Thermal stability; WATER; POSS; Polyurethane; Elastomer; Thermal degradation; Condensation reaction; Property composition relationship; Silsesquioxane polymer; Thermoplastic rubber; Silsesquioxane copolymer; Experimental study; Urethane copolymer; Thermal stability; Polyurethane elastomer; Thermal properties; Preparation; Reaction mechanism; Chemical properties; Block copolymer
• ISSN: 0141-3910; 1873-2321
• DOI: 10.1016/j.polymdegradstab.2010.02.021

Reported here is the synthesis of a series of polyurethane/POSS nanohybrid elastomers, the characterisation of their thermal stability and degradation behaviour at elevated temperatures using a combination of thermogravimetric Analysis (TGA) and thermal volatilisation analysis (TVA). A series of PU elastomer systems have been formulated incorporating varying levels of 1,2-propanediol-heptaisobutyl-POSS (PHIPOSS) as a chain extender unit, replacing butane diol. The bulk thermal stability of the nanohybrid systems has been characterised using TGA. Results indicate that covalent incorporation of POSS into the PU elastomer network increases the non-oxidative thermal stability of the systems. TVA analysis of the thermal degradation of the POSS/PU hybrid elastomers have demonstrated that the hybrid systems are indeed more thermally stable when compared to the unmodified PU matrix; evolving significantly reduced levels of volatile degradation products and exhibiting a ∼30 °C increase in onset degradation temperature. Furthermore, characterisation of the distribution of degradation products from both unmodified and hybrid systems indicate that the inclusion of POSS in the PU network is directly influencing the degradation pathways of both the soft and hard-block components of the elastomers: The POSS/PU hybrid systems show reduced levels of CO, CO 2, water and increased levels of THF as products of thermal degradation.