The article is devoted to innovative approaches to the use of environmentally safe polymer binders in the production of thermal insulation materials (TIM) based on vegetable raw materials. The relevance of the work is due to the need to replace traditional synthetic polymers such as polyurethane foam, polystyrene foam, and mineral wool, which in the process of operation emit toxic substances with cumulative properties. Research shows that the use of biopolymers and renewable resources, such as castor oil-based polyurethane resins and casein adhesives, can significantly reduce environmental burdens and improve material safety. Special attention is given to thermoplastic and thermoset matrices, their properties, and applications in composite materials. Thermoplastics such as polyethylene and polypropylene have high impact resistance and recyclability but are limited in application due to the difficulty of processing and high melting point. Thermoset matrices, despite their high strength and resistance to chemical attack, are molded only once, making them difficult to recycle. This article discusses the advantages and disadvantages of different polymer binders and their prospects in the context of environmental sustainability and the efficiency of thermal insulation materials. The research is aimed at improving the physical and mechanical properties of composites and optimizing production processes to create affordable and environmentally friendly thermal insulation materials.

Keywords: innovative approaches, environmentally safe polymers, thermal insulation materials (TIM), plant raw materials, biopolymers, renewable resources, thermoplastics, thermosetting matrices, environmental sustainability, physical and mechanical properties

The article is devoted to the systematic approach to the development of new composite building materials with lignocellulosic fillers, special attention is paid to the study of their thermal stability. The desire to increase the thermal stability of cellulosic materials implies the use of various modification methods, including acetylation and the use of flame retardants. The properties of monoethanolamine (NB)-trihydroxyborate (MEATHB) as a modifier to improve the fire resistance of thermal insulation materials based on stems of Sosnovsky's borer have been investigated. Experimental methods include thermogravimetric and differential scanning analysis, which allowed the evaluation of thermal decomposition and thermochemical transformations of the raw materials used. The results show that pre-modification using MEATGB shifts the peaks of cellulose thermo-oxidative decomposition temperatures to higher ranges, indicating an increase in the thermal stability of the materials. It is also found that the combination of modification using polyurethane and casein binders improves the thermostatic characteristics, which opens new perspectives for the creation of biostable thermal insulation materials. Thus, the results of this work can serve as a basis for further research and development aimed at creating innovative composite materials with high temperature resistance and biostability using available and environmentally friendly plant raw materials.

Keywords: composite materials, lignocellulosic fillers, thermal stability, monoethanolamine(NB)-trihydroxyborate, biostability, thermal insulation materials, thermogravimetric analysis, polyurethane binder, casein glue

In recent decades, awareness of the environmental, social and economic crisis, both at the national and international levels, has prompted researchers to develop new, low-cost composites that are more environmentally friendly and safer for humans, using plant materials as reinforcing elements. Compared to conventional synthetic reinforcing materials, lignocellulosic fibers have many advantages. In addition to being renewable, inexpensive, widely available and harmless to health, plant fibers have relatively high specific mechanical properties combined with low density. However, there is a problem with the biostability of plant materials used in the production of composite materials, and to solve it, it was decided to pre-modify plant materials using the monoethanolamine (N-B) trihydroxyborate modifier. In order to find out the effect of the modifier on the plant material, the chemical composition of the plant material was determined before and after the modification. Determination of cellulose content was carried out by the nitrogen-alcohol method according to Kurshner and Hoffer; the amount of hemicelluloses was analyzed by treatment with 2% hydrochloric acid, followed by precipitation of furfural obtained by the bromide-bromate method; lignin content was determined by the Clason method using 72% sulfuric acid; and, finally, the content of extractive substances soluble in organic solvents was determined. It should be noted that, compared with the component composition of the raw plant material, there is a change, and this change is noticeable in the amount of lignin after the modification of the raw material and after extraction, which gives a decrease of almost 2.75 times. This is due to the formation of weak esters under the action of the modifier and, most strikingly, a strong increase in the amount of hemicellulose, which contributes to the depolymerization of cellulose macromolecules under the action of the alkaline modifier used. All this allows us to state that the modification of the crushed stems of Sosnowski's hogweed with monoethanolamine (N→B)-trihydroxyborate changes the composition of the components of the lignocarbohydrate complex of the substrate in the direction of reducing the degree of polymerization and the formation of esters.

Keywords: component composition, cellulose, hemicellulose, lignin, extractives, vegetable raw materials, ligno-carbohydrate complex