Current Trends in the Field of Modification Polymers With Fillers Based on Plant Raw Materials (Review)

The review presents the latest research in the development of composite materials based on polymers and fillers derived from plant raw materials. Analysis of literature data has shown that it is most promising to use epoxy oligomers and polyolefins as polymer matrices. Composites based on epoxy resins are modified by a huge number of different fillers of plant origin, which, however, can be divided into three groups: fibers or their waste; a mixture of fibers and agricultural waste; a mixture of powdered crop products and agricultural waste. The use of plant fillers in epoxy oligomers allows not only to solve the problem of waste disposal and reduce the cost of polymer composite materials, but also to modify the complex of their properties. Thus, in most of the analyzed works, a significant increase in physical and mechanical parameters was shown, including tensile strength, elastic modulus, hardness and impact strength. Modification of polyolefins (polypropylene, high- and low-density polyethylene) with fillers from plant materials in many cases leads to an improvement in their deformation-strength properties. The effect on other parameters such as thermostability seems to be ambiguous, as some works show increase of the resistance to elevated temperatures and some studies show a decrease in the degradation temperature. Polymer matrices based on elastomers, polymers of natural origin and polyesters attract much less interest of researchers. However, their modification with fillers of plant origin leads to obtaining materials with good performance characteristics and has prospects for development in the future.