简体中文 English

Location:Home > News > IndustryNews Center

Natural fiber on display at WPC conference

Author:未知 Source:  Updated:2014-09-30 16:09:29 Clicks:
STUTTGART-FELLBACH, GERMANY (Sept. 29, 10:45 a.m. ET) -- Developments in the wood plastic composite profile sector were again one of the major themes at Kassel University’s annual natural fiber reinforced composites sympos

STUTTGART-FELLBACH, GERMANY (Sept. 29, 10:45 a.m. ET) -- Developments in the wood plastic composite profile sector were again one of the major themes at Kassel University’s annual natural fiber reinforced composites symposium, which took place at Stuttgart-Fellbach.

Marc Thometschek, managing director of Belgium-based WPC compound producer Beologic, showed a new window roller blind application it developed with a U.K. company. The project uses profiles comprising a recycled PVC foamed core coextruded with a thin outer WPC layer, which can be brushed and embossed to provide a real wood appearance.

Thometschek said that this combination is easily recycled. Beologic can take back either full length WPC profiles or milled WPC profile materials from its customers for reprocessing into new compounds.

Placing the WPC on the outer surface reverses the trend in the window profile sector – such as the Andersen technology used by Fentech in Switzerland - of placing the WPC in the core of the profile and coextruding it with standard PVC inner and UV-stabilized PVC outer layers.

Thometschek describes the new WPC processing technique as “aesthetic coextrusion”. He said it could be used with both PP and PVC versions, and suggests that the technology may be extended to include foamed WPC core sections.

Most of the German and Austrian WPC profile producers use PP-based WPC compounds. Around 75 percent of Beologic’s production today is in 50 percent wood reinforced PVC types, in no small part due to it being preferred by its major profile industry customer Deceuninck. However, Beologic can also supply PE and PP versions with between 60 and 75 percent woodfiber reinforcement.

Thometschek also said that coextrusion technology enables cost savings to be achieved by using colorants and UV masterbatches only in a thin exterior layer rather than the entire mass of the profile.

Beologic’s present WPC compound capacity amounts to 20,000 metric tons per year, with 2010 sales estimated at 14,000 tons, but Thometschek said that the company’s “vision” is to double capacity to 40,000 tons per year in the future. To that end, the company is working with extrusion machinery producer Hans Weber on tool geometry, material selection and calibration.

Beologic’s development team is also exploring the use of fiber from medium density fiberboard (MDF) for the production of WPC compounds, as well as investigating the use of PLA to create a foamable biodegradable compound and exploring new products based on PS, APS and polybutylene.

The results of a project carried out at between Michigan State University and the IWS materials, plastics and recycling institute at Kassel University were presented to delegates in a poster session, showing that it is possible to expand PLA 10 times into a chemically foamed microcellular foam.

The project partners concluded that, while the expansion ratio and cell size is significantly affected by the addition of wood flour, it should still be possible to save a considerable amount of PLA material in a WPC formulation.

Another compound development project carried out by Kassel University together with the University of the Americas in Puebla,Mexico, described the use of hybrid wood/PAN or wood/PET fibers. These have been shown to improve the mechanical properties of the compound over pure wood fiber WPC, with the researchers claiming that a 25 percent addition of PP-PAN fibers doubles the impact strength of injection molded samples and results in WPCs with an improved stiffness-to-impact-strength.

Werner Krammel, technical sales manager for southern Germany at Plasmatreat, explained how the company’s Openair plasma treatment technology has been used to improve bond strength for foil cladding and painting of WPC profiles. The system is said to overcome typical issues of low surface tension, hydrophobia and non-polar characteristics of polyolefin-based polymer materials Examples of Openair-treated WPC profiles includes products painted with three layers (primer, undercoat and water-based topcoat paint) as well as PUR adhesive and PVC foil wrapping and lamination.