Abstract: Fibers of annual plants e.g. straw for use in forming composite products are improved by hydrothermal treatment at 40° to 120 ° C. with or followed by high shear treatment. The process enables the use of annual plant fibrous materials not hitherto usable successfully.

Abstract: Materials for use in forming composite products are prepared from recycled composite materials and treated by hydrothermal treatment at 40 ° C. to 120 ° C. along with or followed by high shear treatment. The process enables the use of recycled materials not hitherto usable successfully and it is possible to form composite products with less or no additional bonding resin.

Abstract: A method for improving the bondability of annual plant materials to a formaldehyde-based resin including the steps of: (a) providing a straw plant material having a plurality of fibers with each of the fibers surrounded by a waxy and silica layer; (b) extruding the straw plant material in a twin screw extruder while simultaneously subjecting the straw plant material to a thermal treatment with an aqueous solution containing a lignin modifying agent or steam, the thermal treatment being conducted at a temperature between about 40° C. and 120° C., the extruding subjecting the straw plant material to a sufficiently high shear force such that the extruding with simultaneous thermal treatment achieves a substantial defibration of the straw plant material with destruction of the waxy and silica layer and formation of individual fibers and (c) subjecting the treated material to heat and pressure in the presence of the formaldehyde-based resin to form a resin-bonded fiberboard or particleboard.

Abstract: A process is described for the manufacture of tannin-bonded particle- and fiberboard wherein the binding of wood chips and fibers is accomplished by obtaining the formaldehyde necessary for the cross-linking of tannin by the hydrolytic decomposition of the binder present in old particle- or fiberboard. The formaldehyde obtained by hydrolytic decomposition is cross-linked with the tannin by high temperature and moisture during pressing.

Abstract: The invention concerns the waste liquor from the chemical-thermal pulping of fibre boards and particle boards containing bonding agents. The waste liquor is produced through a procedure in which fibre boards and wood particle boards are first chopped into shreds and, in a subsequent step, pulped according to a chemical-thermal procedure which dissolves the wood structure. The liquid remaining after the separation of the cellulose is retained as waste liquor and used as extender for wood adhesives.

Abstract: Durable molded construction parts are disclosed, which are prepared from hydration products of a settable construction material comprising a hydraulically hardening mixture and at least one reinforcing material subject to degradation under alkaline conditions. The construction material has an alkali buffer capacity which does not exceed 0.005 acid equivalents per 100 grams of construction material, as measured in an aqueous suspension of the construction material 24 hours after suspension formation.