Emissionen an flüchtigen organischen Verbindungen aus Faserstoffen zur Herstellung von Faserverbundwerkstoffen

During manufacturing and in use fiber composites emit voltatile organic compounds (VOC). Many factors can affect the emission such as the raw materials used (fibers, polymer, additives), the pulping process applied for pulp production and aging conditions. The work presented deals with emission of VOC from wood fibers as well as medium density fiberboards (MDF) made therefrom. Moreover, the emission from hemp fibers and composites made therefrom was also assessed. The results reveal that the chemical composition of VOC and their amounts depend highly on the raw material (pine wood and hemp straw) used as well as on the pulping process (thermo-mechanical process (TMP) and chemo-thermo-mechanical process (CTMP)) and pulping conditions applied. The objective of further work was to reduce the amount of VOC through adding highly reactive polyphenolic polymers such as condensed tannins during wood and hemp straw pulping. The results indicate that addition of tannins in the CTMP process improves the mechanical properties of the medium density fiberboards and lower theit emission. The emission of hemp fibers and hemp composites prepared therefrom turned out to be very low.