Mathematical Model for Determining the Colorimetric Characteristics of Composite Materials Based on PLA and Wood Filler

Abstract

The environmental concern of many countries seeking to conserve natural resources is driving the development, production and consumption of biodegradable composites. However, in view of their high cost, adding various fillers to composites (such as, wood flour (WF)) is promising. The advantages of using composites with wood fillers are resistance to weathering, environmental friendliness, ease of mechanical processing, and the possibility of waste disposal. To improve the properties and expand the scope of such composites, it is possible to use thermal modification of the filler, which gives wood such properties as: high hardness, water resistance, chemical and biological resistance. Thermal modification consists in heating wood in the temperature range from 150 to 230 °C without oxygen. At the same time, color properties of the material are changed definitely: an increase in the processing temperature affects darkening of wood, which leads to a change in the color characteristics of the last composite. In this regard, a regression mathematical model is proposed for easy color control prediction of the product, which is obtained as a result of composites color analysis based on polylactide (PLA) and the RGB color code. The proposed mathematical model, setting the processing temperature of wood filler, lets predicting the intensities of red, green and blue components for the subsequent visual representation of the last composition color using standard computer programs.