Determination of the structure and composition of clinically important polyurethanes by mass spectrometric techniques

Abstract

SynopsisCurie-point pyrolysis maSS spectrometry (Py-MS) and direct probe pyrolysis high resolution mass spectrometry (Py-HRMS) were used to identify the components and additives used in the synthesis and compounding of Biomer, Lycra Spandex, Tecoflex, and Pellethane. Two types of Biomer were identified (P and Q, our notation) which are composed of poly(tetramethy1ene glycol) (PTMG) capped with 4,4'-rnethylenebis(phenylisocya I re) (MDI) and chain-extended with ethylenediamine (EDA). Both forms contain 4,4'-butylidene-o~s-(6-t-butyl-rn-cresol) antioxidant, and Biomer Q also contains an additive which appears to be a quaternary ammonium chloride salt. Lycra Spandex was found to be identical to Biomer Q, with the exception that a low molecular weight polydimethylsiloxane oil is also present. This silicone oil can be removed by solvent extraction. Tecoflex (type SGBOA) is composed of PTMG capped with 4,4'-diisocyanatodicyclohexylmethane and extended with 1,l-butanediol (BD). An industrial grade and a medical grade of Pellethane were analyzed. Both were composed of PTMG capped with MDI and extended with 1,l-butanediol. The industrial grade also contains an antioxidant, possibly butylated diphenylamine.

Composite Articular Cartilage Engineered on a Chondrocyte-Seeded Aliphatic Polyurethane Sponge

“…11,32 Tecoflex is a proprietary aliphatic polyurethane composed of poly (tetramethylene oxide) and dicyclohexyl methane diisocyanate as deduced by mass-spectrometric techniques. 33 Previous studies have shown that Tecoflex is susceptible to in vivo degradation, characterized as environmental stress cracking through the formation of surface fissures resulting from localized hydrolysis of urethane linkages. 34 Degradation has been shown to contribute to mechanical failure of some Tecoflex-based catheter devices.…”

Effect of toluene extraction on Biomer™ surface: I. ESCA, ATR/FTIR, contact angle analysis and biological properties

“…In particular, the presence of three major additives in different BiomerTM lots [7] has been reported. These additives are: a polysiloxane which may be due to 50 contamination during synthesis of polymer [8]; a high-molecular weight UV stabilizer identified as poly(diisopropylaminomethacrylate-co-decylmethacrylate) (PAM) [9]; and an antioxidant, the 4,4'-butylidene bis(6-t-butyl-m-cresol) [10] known under the commercial name Santowhite Powder (SP).…”