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Surfaces of three European (English oak, ash and Scots pine) and three tropical (teak, cloves and neem) wood species were silylated with chlorotrimethylsilane, octadecyltrichlorosilane, trimethylsilyl N,N-dimethylcarbamate and an alkoxysilane-terminated surfactant introducing diethoxy-silyl groups onto the surface structure. For the study of surface composition, ATR-FTIR and ESCA measurements were performed. The hydrophobicity of the surfaces was studied by contact angle determinations.

This study reports on the smoldering propensity of commercially available barrier fabrics in a small-scale mock-up configuration. Most barrier fabrics are smolder resistant when tested alone over a standard flexible polyurethane foam. However, when covered with a smolderprone cover fabric, most barrier fabrics failed the smoldering ignition test described in the Consumer Product Safety Commission's proposed standard 16 CFR Part 1634. The results of this study suggest that the smolder-prone cover fabrics, when placed on top of a number of barrier fabrics, are capable of releasing sufficient heat to initiate the char oxidation smoldering process of some of the barrier fabrics and subsequently transmit the heat to the underlying flexible polyurethane foam. A smoldering index for barrier fabrics was derived from the measured char volume fraction of the flexible polyurethane foam by varying the barrier fabric component in the flexible polyurethane foam/barrier fabric/cover fabric mock-up systems, while holding the other two components constant. The smoldering index for self-extinguishing barrier fabrics was 0. Barrier fabrics with smoldering index of 1 or more resulted in sustained smoldering in the flexible polyurethane foam. The smoldering propensity of barrier fabrics and the amount of heat transmitted to the flexible polyurethane foam varied depending on the barrier fabric structure, fiber content, air permeability, and bulk density. Flame-retardant treatments and use of char-forming fibers showed a greater tendency for barrier fabric smolder in the presence of the smolder-prone cover fabric. Barrier fabrics with char-forming fiber blends had greater smoldering propensity as compared to barrier fabrics with low charring fiber Downloaded from blends. The lower the smoldering propensity of the barrier fabric, the less likely was the development of sustained smoldering in the flexible polyurethane foam.

The objective of this study was to evaluate whether polyurethane foam (PUF) could be produced as a Standard Reference Material for ultimate use in a standard test intended to ensure the smoldering performance of commercially available upholstered furniture. For this purpose, PUF was produced by a commercial manufacturer and its smoldering propensity was evaluated. The experimental design was organized into four parts or "Iterations". In Iteration 1, the results showed that smoldering intensity was dominated by foam morphology (cell size, strut thickness and length, open vs. closed cell structure, etc.), which overrode effects of chemical composition for the range of polyols and surfactants studied. In Iteration 2, the morphology of the foam was controlled by varying the processing parameters, that is, the tin catalyst content, water content and mixing head pressure. The results showed that smoldering increased with air permeability but that a better morphological descriptor of the foam structure was required to fully characterize smoldering in the high permeability range (i.e., in PUF with a dominantly open-cell structure). In Iteration 3, it was determined that for these PUFs, smoldering was controlled by cell size. The feasibility of a reference material with well-characterized and reproducible smoldering is linked to the ability to manufacture an open-cell PUF with a well-defined cell size and density. Preliminary data from Iteration 4 indicates that PUFs with consistent smoldering can be produced on a commercial scale manufacturing line.