Primary Pyrolysis Products of Hydroxy-Terminated Polybutadiene

Abstract

This is the first report on the analysis of primary degradation products of a widely used commercial propellant binder, viz. hydroxy-terminated polybutadiene (HTPB), which has been carried out by direct pyrolysis mass spectrometry. The mechanism of degradation involves a radical process forming cyclic compounds as well as β-CH transfer reactions to form linear oligomers. On the basis of heats of formation data, it was found that the formation of 1,3-butadiene monomer is not favored during the primary chain scission process. However, its formation appears to emanate from the dissociation of high molecular weight cyclics/linear oligomers. In the presence of strong oxidizers such as ammonium perchlorate, the degradation pattern of HTPB, as observed in pyrolysis-gas chromatography/mass spectrometry analysis, is significantly affected, indicating its influence on HTPB degradation.

Hydrophobic, Water-Dispersible Polyurethane: Role of Polybutadiene Diol Structure

“…[16][17][18] There are several methods published by us and other groups to modify the HTPB backbone with varieties of functionality to enhance the physical properties like energy output, [19][20][21] Having accomplished good properties of HTPB by modifying backbone, we plan to utilize this new diol (called HTPB-DNB) to make PU based materials for coating applications with an aim to achieve thermally and mechanical strong coating. Also the presence of this extra -NO2 functional groups and phenyl rings might help us in improving the hydrophobic characteristic of the final resulting PU materials.…”

Preparation of a P(THF-co-PO)-b-PB-b-P(THF-co-PO) triblock copolymer via cationic ring-opening polymerization and its use as a thermoset polymer

“…5,6 These results are attributed to the activated monomer (AM) mechanism. [12][13][14][15][16][17] Given that a large number of unsaturation groups exist in the backbone of HTPB, the polymer exhibits some fascinating chemical and physical properties. Thus, one important advantage of AM polymerization is that back-biting reaction could be eliminated because of the absence of active species at the end of growing chain.…”

Cloisite 15Aº nanoclay as an effective PTC for the epoxidation of hydroxyl terminated polybutadiene (HTPB)

“…Among the engineering polymers, the hydroxyl-terminated polybutadiene (HTPB) is widely used as a binder in the formulation of adhesives, solid rocket propellants, elastomers, sealants etc., due to its unique physicochemical properties namely, thermal stability, performances under dynamic load, pyrolysis resistance, elasticity, toughness, and durability [3] . These properties are performed by introducing of one or more epoxy functional groups in non-polar non-conjugated HTPB main chain [4] .…”