Patent DE-102007057907-A1 (DE)
Title: Producing natural fiber composite material/product from fiber composite material useful as plastic molded parts, comprises producing a composite mass containing fiber material in mixture with plastic in mixing- and comminuting device
Inventor: HIENDL HELMUT
IPC: C08J5/04
Filed: 2007-11-29
Abstract: The method for producing a natural fiber composite material or a product (1) from a fiber composite material useful as plastic molded parts, comprises producing a composite mass containing the fiber material in mixture with plastic in a mixing device and a comminuting device (5) by adding fiber component and a first thermoplastic component by mixing, melting and homogenizing, and producing the natural fiber composite material and/or the product by adding a second plastic component, so that the plastic portion in the natural fiber composite material and/or the product is large. The method for producing a natural fiber composite material or a product (1) from a fiber composite material useful as plastic molded parts, comprises producing a composite mass containing the fiber material in mixture with plastic in a mixing device and a comminuting device (5) by adding fiber component and a first thermoplastic component by mixing, melting and homogenizing, and producing the natural fiber composite material and/or the product by adding a second plastic component, so that the plastic portion in the natural fiber composite material and/or the product is larger than the plastic portion in the composite mass. The fiber component contains different organic and/or inorganic fibers. The second plastic component is different from the first component regarding type and/or characteristics. The second component is highly liquid than the first component in the melted condition. An adhesion-modifying additive is added during the production of the pre-mixture or the pre-product and/or during the processing of the pre-product in the fiber composite material and/or in the products. An adhesion-modifying plastic is used as the second component. In the first mixing phase or premixing phase, a drying of the natural fiber component is carried out up to a remaining humidity content of = 5%. The adhesion modification is caused by maleic acid hydride grafted polymer. The addition of the second plastic component is carried out by mixing the component into the still hot pre-product. The second component is supplied to the mixing device and the comminuting device. The addition of the second component is carried out when premixing of the second component reaches the measuring temperature or the melting temperature and/or the remaining humidity content of the premixture and/or the natural fiber component is = 5%. A mixture consisting of pre-product or the premixture in the form of granulates (2) and the second component are supplied to a processing machine (4) or -mechanism for the production of the products from the fiber composite material. The processing machine or -mechanism is an extruder, a spraying machine or a press installation. The second plastic component is admitted as melt. The addition of the second plastic component is carried out over a heated dosing device (4.1).