Composite material comprising bio-filler and specific polymer

Abstract

A composite material comprising 10-98 wt. % of a bio-based particulate or fibrous filler and at least 2 wt. % of a polyester derived from an aliphatic polyalcohol with 2-15 carbon atoms and a polyacid, wherein the polyacid comprises at least 10 wt. % of tricarboxylic acid. Preferably, the filler is in the form of particles, fibers, and/or random or non-random layers. A plant-based filler may be used, in particular a cellulosic or lignocellulosic material, more in particular one or more materials selected from wood chips, wood flakes, sawdust, pulp, e.g., pulp of (recycled) paper or other fiber pulp, and plant-derived fibers such as cotton, linen, flax, and hemp. An animal-derived filler, in particular an animal-derived fiber such as wool, hair, silk, or feathers may also be used. Preferably the polyalcohol is selected from one or more of glycerol, sorbitol, xylitol, mannitol, 1,2-propane diol, 1,3-propane diol, and 1,2-ethane diol, in particular glycerol. The polyacid preferably is an aliphatic diacid or triacid with 3-15 carbon atoms. Examples of suitable acids include citric acid, succinic acid, and itaconic acid. The composite material according to the invention has fire-retardant properties, which makes it particularly suitable for applications where fire-retardancy is an issue.