Research progress of polymer composites filled with tea biomass

Abstract: The researches and applications of biomass materials have always been the interest of people, due to the advantages of low-cost, non pollution, regeneration and so on. Tea biomass is the general name of waste dominated during the cultivation, processing, deep processing and consumption processes of tea. The tea biomass includes 1)dead-wood, fallen leaves, pruning branches and leaves, seed shells and other tea residues produced during tea cultivation; 2)fannings, thick stems, old stems and tea ash produced during tea processing; 3)tea residues and tea oil cakes produced during deep processing of tea beverage, instant tea, tea polyphenols and tea oil; 4)tea leaves after drinking of tea. A large number of tea residues are produced during the process of planting, production, processing and consumption of tea. China is the biggest producer and consumer of tea all over the world. The cultivation area and yield of tea of China were more than 2.9×106 hm2 and 2.6×106 t in 2019, respectively, which accounts for 60% and 50% of the world's area harvested and yield of tea. The worldwide consumption of tea is about 6 million tons annually, and the amount of tea biomass produced during the tea industry reached up to 5×106 t per pear merely in china, most of which were treated as agricultural waste, resulting in both environmental pollution and enormous natural resource waste. Therefore, the research and application of tea waste would be great benefit to the environment management and developpment of tea industry. The tea biomass resources showed a hollow porous structure and were rich in cellulose, lignin, hemicellulose, tea polyphenols, theanine and other useful components. Traditionally, the tea biomass were mainly used as raw materials to extract active components, plant growth fertilizers, animal feeds and environmental adsorption materials. It has extensive application potential in agriculture and animal husbandry, health care, food processing, environmental protection and composited materials. With the developpment of research focused on the tea biomass, the composites prepared by the combination of tea biomass with polymers have been developped rapidly and widely in recent years because of their excellent processing and application performance, and have became the most important part of tea biomass based materials. In order to clarify the current research status of the tea biomss/polymer composites, this paper introduced the characteristics and chemical composition of the tea biomass resources first, and then the advances in research of tea biomass filled different polymers composites were recommended, and the progress of application in particleboard, wood-plastic materials, sound-absorbing materials, rubber based composites, pulp and paper making, wastewater treatment and functional food of polymer composites filled with tea biomass were also overviewed. In addition, the future research of tea biomass resources are pointed out, which includes 1)developing comprehensive and integrated utilization technology of tea biomass; 2)exploiting the research in flame retardant, electrical, thermal, antibacterial and deodorizing properties of the tea biomass filled resin materials; 3)enhancing the application research in tourism, health preservation, decoration and other fields of the tea biomass filled polymer composites; 4)studying the influence and mechanism of the biochemical components changes of tea biomass on the taste, appearance and health performances of the tea functional foods.