High Thermal Insulation Properties Research Articles

High thermal insulation and high strength SiBCN@SiC double network ceramic composite aerogel

Silicon carbide (SiC) fiber materials prepared by precursor conversion method have attracted extensive attention in recent years due to their excellent high temperature resistance and thermal insulation properties. Herein, a novel SiBCN/SiC dual network ceramic composite aerogel with the three-dimensional (3D) porous SiC fiber network obtained by direct electrospinning as the first network and SiBCN aerogel as the second network was prepared by combining electrospinning with sol-gel technology and supercritical drying technology. The microstructure, phase composition, pore size distribution, compressive resistance, thermal insulation and related mechanisms of the 3D SiC fiber network and composite aerogel at different heat treatment temperatures were investigated in detail. The results show that the constructed double-network structure can make up for the heat transfer problem of a single SiC fiber network and further reduce its thermal conductivity, so that the prepared composite aerogel exhibits a lower thermal conductivity (∼0.0316 W m−1 K−1). In addition, the unique double network structure endows the composite aerogel with excellent compressive properties (2.56–2.89 MPa).

Improved creep resistance of AZ91 magnesium alloy after the micro arc oxidation process

AZ91 Mg alloy has a wide range of applications in the automotive industry, although its use is restricted to powertrain applications due to its low creep resistance. In this study, the effect of the micro arc oxidation (MAO) coating on the creep resistance of an AZ91 Mg alloy was investigated to take advantage of the coating layer with high thermal insulation properties. In this context, the MAO process was applied to AZ91 Mg alloy using a bipolar pulsed DC power supply. The creep tests were conducted at different temperatures (150–200 °C) and stresses (25–90 MPa) for the bare and coated samples, and the minimum creep rates were determined. It has been shown that the MAO coating reduces the creep rate of the bare alloy by 35%–84% depending on the temperature and the stress due to the stress-reducing effect and thermal barrier properties of the MAO coating. Based on the calculated creep activation energy and stress exponents, creep mechanisms were proposed for the bare and coated alloys. Effective activation energy was also calculated and lattice diffusion-controlled dislocation climb was determined to be the effective creep mechanism for both samples at lower stresses, while pipe diffusion-controlled dislocation climb was effective at higher stresses.

Effects of Carbon Nanotubes on Thermal Behavior of Epoxy Resin Composites

Human society’s need to build low-weight, high-strength and durable structures has increased the demand for composite materials. In this case, composites are used where high mechanical strength, low weight, sound and thermal insulation properties are required. One of the most important issues now is designing materials and coatings aimed at reducing heat loss and resisting high temperatures. One way to address this problem is to develop a technique for preparing and applying composite materials that slow down their heating applied to a surface. In this study, carbon nanotubes (CNTs) reinforced composites were fabricated using silicone molding to be applied to honeycomb sandwich structures. To determine the effect of CNTs on the thermal behavior of the sandwich panels, different weight percentages of this material (0.025, 0.05. 0.075 wt.%) were added to the epoxy resin. The results showed that the thermal stability of the epoxy composites was directly related to the increase in the percentage of CNTs as the CNT content increased to 0.075 wt.%, and the thermal degradation temperature of the epoxy composites increased by 14 °C. In addition, the energy absorption increased by 4.6% with an increase in CNTs up to 0.075 wt.%. Density measurements showed that the density of the nanocomposite samples increased by adding CNTs to pure epoxy resin. The actual densities of the samples reinforced with 0.025, 0.05, and 0.075 wt.% CNTs are 0.925, 0.926, and 0.927 of the theoretical density, respectively. Since the CNT dispersion uniformity in the epoxy matrix can significantly affect the properties of the composites, in this study, a new method of dispersing CNTs in the epoxy resin matrix resulted in higher thermal conductivity while using lower amounts of CNTs compared to other studies. The storage modulus of the epoxy matrix composites reinforced with 0.05 wt.% in this study was 25.9% and 6.9% higher than that from the previous study reinforced with 0.1 wt.% and 0.25 wt.% CNTs, respectively. Furthermore, the tanδ and loss modulus of the composite reinforced with 0.05 wt.% CNTs in this study were 52% and 54.5% higher than that from the previous study with 0.1 wt.% CNTs, respectively. This study provided an optimal approach for designers and engineers who want to effectively design their composite honeycomb sandwich structure with better thermal properties.

Properties of Lightweight Insulating Boards Produced from Triticale Straw Particles.

Insulating materials made from straw are becoming increasingly popular in the construction industry. Straw can be used in the construction of buildings as uncompressed straw chips or in the form of compressed panels. This study aimed to determine the possibility of manufacturing boards from straw particles with densities in the range of 150-400 kg/m3, allowing favorable mechanical properties while simultaneously providing high thermal and acoustic insulation properties. The study also analyzed the influence of the degree of carpentry density on the quality of the manufactured boards. The study shows that insulation boards can be produced from straw particles with satisfactory properties already at densities in the range of 200-150 kg/m3. Boards with this density have a compressive strength of 150 kPa, thermal resistance of 0.033-0.046 W/(m·K), and a sound absorption coefficient above 0.31.

Janus microbial membrane constructed by multiple biological self-assembly for photothermal conversion

Biological self-assembly as a kind of biological spontaneous behavior presents low energy consumption and high efficiency. In this work, biomass membrane is closely combined with carbon membrane derived from microorganism by biological self-assembly, forming Janus membrane (FAS-MC@M). The biomass-derived carbon membrane is endowed with superior photothermal conversion efficiency, also with the enhanced salt resistance via its hydrophobic nature and salt excretion domains. On the other hand, the biomass layer with good hydrophilicity and abundant capillary transport pipes ensure rapid water transfer to the Janus interface, conducing to stable heat exchange. The intrinsic micropores of the mycelium fiber can secure the reliable salt ion exchange between the tube water and bulk water during evaporation, which inhibit salt crystals formation as well. Meanwhile, biomass layer also reveals the relatively high thermal insulation properties, which can lower heat loss of the carbon membrane and improve the heat accumulation effect. For oily sewage, the biomass layer is also effective in protecting the photoheat exchange interface (carbon membrane) from oil pollution. In fact, the Janus evaporator in this work achieved 3.2 kg m-2h−1 evaporation rate under one solar intensity, showing desirable evaporation desalination potential.

Investigations of Three‐Layer Systems Intended for Protective Clothing for Prematurely Born Babies

AbstractOne of the most significant problems occurring among premature babies is high transepidermal water loss and associated heat loss. To prevent this problem protective clothing for premature babies is developed which consists of a membrane that allows partial transmission of water vapor, combined with other textile materials. The purpose of this work is to characterize two pre‐selected three‐layer systems in terms of biophysical properties that fulfill their requirements for premature infants. Samples of materials are investigated to determine biophysical comfort (tests of thermal resistance, water vapor resistance and air permeability), mass per unit area and thickness. In order to visualize the structure and chemical composition of the tested materials, Scanning Electron Microscopy (SEM) were performed. The mechanical properties of the investigated materials and the evaluation of the total hand value were also characterized; the samples were tested on a Kawabata Evaluation System (KES) device. Protective garments designed for premature babies should be characterized by high thermal insulation and moisture barrier properties. In addition, it should have optimal air permeability properties and fairly low surface weight in order not to burden the baby's delicate skin.

Ambient pressure dried silica aerogel – Melamine foam composite with superhydrophobic, self-cleaning and water remediation properties

With their low density, high surface area and thermal insulation properties, silica aerogels are proper candidates for water remediation or thermal insulation applications. However, their fragility, lengthy and costly fabrication process restricts their application. The inclusion of a flexible melamine foam (MF) along with a co-precursor system consisting of monomeric methyltrimethoxysilane (MTMS) and polymeric polyvinyltrimethoxysilane (PVTMS) can make the fabrication process feasible and improve the durability of aerogels. Also, PVTMS with a doubly-crosslinked network brings mesoporous structure and high surface area to MF. MTMS alters the hydrophilic nature of MF to superhydrophobic, without surface modification steps.Varying concentration of PVTMS and MTMS were used to fabricate the MF- aerogel composite. Acid and base catalysts were used for the hydrolysis and condensation. The MF-aerogel composite was obtained using ambient pressure drying, and the overall fabrication process took around 48 hrs.The inclusion of MF enabled the ambient pressure drying and brought flexibility for silica aerogels. On the other hand, the presence of mesoporous aerogels improved the thermal insulation properties of MF (λ ∼ 0.027 W·m−1·K−1), making it superhydrophobic (θ ∼ 160°), self-cleaning, and moisture resistant. Excellent oil adsorption (up to 36 g·g−1) and oil–water separation performance (oil flux of 120,000 L·m−2·hr−1) of MF-aerogel composite were also confirmed.

Versatile spider-web-like cross-linked polyimide aerogel with tunable dielectric permittivity for highly sensitive flexible sensors

With the development of intelligent electronic power systems, the performance of flexible electronic sensors with portability and miniaturization is increasingly in demand. It is extremely challenging to achieve high modulus and high elasticity of polymer matrix simultaneously due to the inherent strength-elasticity conflict of elastic polymer. Here, a series of “spider-web-like” cross-linked polyimide aerogels (CPAs) had been successfully prepared. Benefiting from the robust dynamic network structure, the CPAs exhibited excellent compressive resilience, tunable dielectric permittivity, high thermal insulation property (λ = 0.040 W/m∙K) and modulus (E = 1073 KPa). Additionally, due to the excellent resilience of the CPAs and tunable permittivity, a CNTs/CPA-3 composite aerogel-based strain sensor obtained by assembling the CPA-3 with carbon nanotubes (CTNs) possessed synergistically enhanced sensitivity, high selectivity and “multi-touch” stress detection, without deterioration even after 2000 cycles. Furthermore, the established mathematical model revealed the internal mechanism of the synergistic enhancement of sensing performance of sensor with strain-controllable permittivity. Thus, the fabricated CPAs might be an ideal substrate material for flexible electronic sensors in electronic power systems, and the mathematical model established could also provide a reliable reference for improving the sensitivity and detection limits of sensors.

Development and characteristics of multifunctional ultra-lightweight engineered cementitious composites incorporating cenospheres and PE fibre

Ultra-lightweight, high ductility, high strength, and multi-functionality are recent development trends in concrete. This study proposed a design concept of multifunctional ultra-lightweight engineered cementitious composites (ULW-ECCs) without functional fillers using fly ash cenosphere (FAC) and polyethylene (PE) fibre, which has heat insulation, self-sensing, and self-healing functions. The mechanical (tension, compression, flexure) and corresponding self-sensing properties under monotonic and cyclic loading, self-healing, thermal conductivity, and thermal effusivity properties were examined. The ULW-ECCs were developed based on the maximum packing density of the matrix, which showed high pseudo-strain-hardening indices and had an apparent density of 1055–1333 (Oven-dry density: 946–1261) kg/m3, compressive strength of 36–58 MPa, and a tensile strain capacity of 4%–8% under standard curing condition. With the use of FAC with a highly stiff shell, the ULW-ECCs show high strength and high thermal insulation properties. ULW-ECCs incorporating FAC show excellent self-sensing properties without any conductive fillers under compression, bending and tension. The electromechanical behaviour was consistent and repeatable during cyclic and monotonic loading processes, and a microstructure model was used to explain the self-sensing mechanism. The cement paste in the matrix can form a 3D-like honeycomb structure because a large number of FACs evenly divide the cement paste, which shows sensitive self-sensing ability. Additionally, the multiple micro-cracks of ULW-ECCs show excellent self-healing properties. Optical microscope and SEM analyses of ULW-ECC were used to explain the results. The developed multifunctional ULW-ECCs without functional fillers would be a promising material for sustainable development.

Paper-based building envelopes – Thermal and environmental properties of original envelope designs

Paper-based materials, due to their availability, environmental benefits and high thermal properties, have already been implemented in several building envelope designs. However, most of them either did not optimise the use of the material or did not provide sufficient thermal insulation for use in permanent buildings. The presented research analyses six original paper-based building envelope core proposals, suitable for use in permanent buildings in temperate climate of Europe, in terms of thermal and environmental efficiency. Proposals include cores with embedded paper tubes structural elements, timber-cardboard studs and sandwich designs. The heat transfer coefficient of the envelopes was obtained for repeatable modules via 2D computer simulations (ThermCAD software), and the environmental impact was assessed for a representative square metre of the envelope via LCA analysis, based in ecoinvent 3.8 database. All analysed designs showed high thermal insulation properties and met the requirements for Umax = 0.20 W/m2K, did not cause the risk of surface condensation, nor have excessive thermal bridges. The analysed building envelope designs based on embedded frame wall structure showed environmental superiority over conventional envelopes (timber frame and SIP panels). The research may serve as a proof of concept, for using paper-based building envelopes in sustainable architecture.

Elevated temperature and performance behaviour of rice straw as waste bio-mass based foamed gypsum hollow blocks

The present study explores mechanical, thermal, acoustic, and fire performance evaluation of locally available rice straw as waste bio-mass in foamed gypsum hollow blocks. Two-core hollow gypsum blocks with various agro-waste compositions have been studied in detail and presented. Aluminum sulphate and potassium alum in 1:1 ratio are used as foaming agents in gypsum blocks. The density of two-core hollow blocks varies from 1070 to 730 kg/m3 for 0–15 wt% rice straw addition. The compressive strength of solid cubes and two-core hollow blocks lies in the range of 4.6-1.4 MPa and 2.2–1.1 MPa respectively. Whereas, the thermal conductivity lies between 0.15 and 0.07 W/m.K. exhibiting excellent thermal insulation. The sound transmission class (STC) of straw based foamed gypsum varies over the range of 23 to 20 dB for 20 mm thick with 0–15 wt% agro-waste added samples. The 5 wt% foamed rice straw gypsum sample has shown resistance to the surface spread of flame and the wallette unit of 600 mm × 600 mm has 70.5 kN of load carrying capacity at 800 °C. The foamed agro-waste-based hollow gypsum blocks may be used as a potential building material for non-load bearing wall application owing to its high thermal insulation, moderate acoustic and excellent fire retardant properties.

Investigating the thermal conductivity and flame-retardant properties of BN/MoS2/PCNF composite film containing low BN and MoS2 nanosheets loading

Cellulose has attracted considerable attention as a potential substitute for plastics. However, the flammability and high thermal insulation properties of cellulose contradict the unique requirements for highly integrated and miniaturized electronics i.e., rapid thermal dissipation and efficient flame retardancy. In this work, cellulose was first phosphorylated to achieve intrinsic flame-retardant properties, and subsequently treated with MoS2 and BN, ensuring efficient dispersion throughout the material. Via chemical crosslinking, a sandwich-like unit was formed, in the order of BN, MoS2, and phosphorylated cellulose nanofibers (PCNF). The sandwich-like units were further self-assembled, layer-by-layer, to successfully create BN/MoS2/PCNF composite films exhibiting excellent thermal conductivity and flame retardancy, and comprised a low MoS2 and BN loading. The thermal conductivity of the BN/MoS2/PCNF composite film containing 5 wt% BN nanosheets was higher than that of neat PCNF film. The combustion characterization of BN/MoS2/PCNF composite films revealed highly desirable properties that were far more superior than the BN/MoS2/TCNF (TCNF, TEMPO-oxidized cellulose nanofibers) composite films. Moreover, the toxic volatiles that escaped from flaming BN/MoS2/PCNF composite films were significantly reduced compared to that of the BN/MoS2/TCNF composite film alternative. The thermal conductivity and flame retardancy of BN/MoS2/PCNF composite films have promising application prospects in highly integrated and eco-friendly electronics.

Natural sub-bituminous coal as filler enhances mechanical, insulation and flame retardant properties of coir-polypropylene bio-composites.

Additives provide substantial improvement in the properties of composites. Although bio-based composites are preferred over synthetic polymer and metal-based composites, they do not have the requisite properties to meet specific needs. Hence, organic, inorganic and metallic additives are included to improve the properties of bio-based composites. Coal is a readily available resource with high thermal insulation, flame resistance and other properties. This work demonstrates the addition of 20-30% natural sub-bituminous coal as filler for coir-reinforced polypropylene (PP) composites and exhibits an increased tensile strength by 66% and flexural strength by 55% compared to the composites without any filler. Such composites are intended for insulation applications and as a replacement for gypsum-based false ceiling tiles. Various ratios of coal samples were included in the composites and their effect on mechanical, acoustic, thermal insulation, flame and water resistance have been determined. A substantial improvement in both flexural and tensile properties has been observed due to the addition of coal. However, a marginal improvement has been observed in both thermal conductivity (0.65W/mK) and flame resistance values due to the presence of coal. Adding coal increases the intensity of noise absorption, particularly at a higher frequency, whereas water sorption of the composites tends to decrease with an increase in the coal content. The addition of coal improves and adds unique properties to composites, allowing coir-coal-PP composites to outperform commercially available gypsum-based insulation panels.

Geopolymer as an Innovative Material for Green Roofs - A State-of-the-Art Review

To help minimize water temperature variations and stop excessive evaporation, effective insulation materials are frequently needed during the design and construction of ponds. In contrast to conventional materials, geopolymer mortars have great insulating qualities, making them an attractive option. An alkaline activator and aluminosilicate materials react chemically to create geopolymers, which have a three-dimensional network structure and high thermal insulation properties. Geopolymer mortars are used in ponds to promote energy efficiency and sustainability while also improving temperature stability and reducing water loss from evaporation. An alkaline activator and aluminosilicate materials react chemically to create geopolymers, which have a three-dimensional network structure and high thermal insulation properties. The use of geopolymer mortars as an insulating material in pond construction is discussed in this abstract, along with its composition, characteristics, and advantages over more conventional choices. Geopolymer mortars are used in ponds to promote energy efficiency and sustainability while also improving temperature stability and reducing water loss from evaporation. The utilization of geopolymers as cutting-edge insulating materials for structures with green roofs is thoroughly examined in this publication. As sustainable construction techniques become more prevalent, selecting the right insulating materials is essential for enhancing energy efficiency and overall building performance. Geopolymers, which can be produced from industrial waste or natural resources, offer appealing properties for green roofs, such as the ability to lessen the impact of urban heat islands, superior thermal insulation, and fire resistance. This study assesses the advantages, challenges, and potential impact of geopolymer-based insulating materials on green construction practices.

Nanosized Hexagonal Boron Nitride and Polyethylene Glycol-Filled Leathers for Applications Demanding High Thermal Insulation and Impact Resistance.

Leather is a niche material used for upholsteries, gloves, and garments due to its high durability, flexibility, and softness properties. The inclusion of nanoparticles in the leather matrix provides multifunctionality for high-performance applications. Herein, we synthesized hexagonal boron nitride (h-BN) nanoparticles via a single-step hydrothermal synthesis and treated the leather after dispersing in polyethylene glycol (PEG) to yield h-BN/PEG-treated leathers. Atomic force microscopy and high-resolution transmission electron microscopy analysis ascertained the particle size of 30-50 nm for as-synthesized h-BN nanoparticles. h-BN nanoparticles along with PEG were successfully incorporated into the leather matrix, and this was confirmed by surface and morphological studies using field emission scanning electron microscopy/energy-dispersive X-ray analysis and Fourier transformed infrared spectroscopy. Leathers treated with h-BN/PEG were studied for insulation against heat and cold, and the results displayed improved thermal insulation properties compared to the control leathers. The dynamic mechanical analysis of control and treated leathers demonstrated higher storage modulus, loss modulus, and tan δ values for h-BN/PEG-treated leathers, signifying an increased energy absorption and dissipation potential, which was further ascertained by the low-velocity drop-weight impact resistance test. Thus, the results of this study open up new prospects for h-BN/PEG-treated leathers in strategic applications demanding high thermal insulation and impact resistance properties.

A high thermal stability core–shell aerogel structure for high-temperature solar thermal conversion

Silica aerogel can be applied to the concentrated solar power (CSP) plants to achieve a high operation temperature due to the high optical transparency and thermal insulation properties. However, the insulation capacity of aerogel at high-temperature will deteriorate rapidly due to the damage of the porous structure. In present study, a transparent aerogel consisting of SiO2/Al2O3 core–shell particles was proposed. The structure-dependent radiative properties were predicted through the combination of Discrete Dipoles Approximation (DDA) and Monte Carlo (MC) method. The core–shell aerogel achieves a higher solar transmittance than the alumina aerogel. The evaluation parameter of greenhouse selectivity was introduced to assess the aerogel performance by considering the solar transmission and infrared extinction simultaneously. An optimal design of SiO2/Al2O3 core–shell aerogel at different temperatures was conducted. Compared with the pure alumina aerogel, a maximum enhancement of 22.6% in greenhouse selectivity was achieved by the core–shell aerogel with ϕ = 95% and r1/r2 = 0.4 at 700 °C. This work provides a promising method to achieve a high-efficient transparent thermal insulating aerogel for high-temperature CSP plants with high thermal stability.

Robust passive daytime radiative coolers based on thermally insulating and spectrally selective composite aerogels with designed fiber-reinforced porous architecture

Passive daytime radiative cooling (PDRC) is an emerging energy conservation technology that spontaneously cools a surface by reflecting solar radiation and emitting excess heat to the cold space through the infrared atmospheric transparency window. A facile strategy to fabricate robust passive daytime radiative coolers based on thermally insulating and spectrally selective composite aerogels are demonstrated. The composited aerogels are constructed by P(VdF-HFP) matrix with abundant micrometer-scale air voids inside and surface modified chopped glass fibers randomly distributed in the porous polymeric matrix. Glass fibers act as skeleton are beneficial for enhancement of the rigidity, compressive strength, and flame retardancy of aerogels to satisfy practical PDRC applications. With a glass fiber mass ratio of 20 %, the aerogel can reach a high average solar reflectance of 0.951 and a high long-wave infrared (LWIR) emissivity of 0.954. By performing rooftop measurements, temperature decrease up to 8.05 °C is experimentally achieved under a high solar radiation (∼946 W m−2) at midday time (12:00–14:00). The promising cooling performance comparable to those of state-of-the-art radiative coolers is attributed to the efficiently scattering ability of sunlight by abundant air voids, and the high thermal insulation property to weaken parasitic heat gain from the ambient air.

Highly thermally conductive, electrically insulated and flexible cellulose nanofiber-based composite films achieved via stereocomplex crystallites cross-linked graphene nanoplatelets

Synchronously achieving high thermal conductivity, electrical insulation and excellent mechanical properties in one flexible thermal management material is still a great challenge. In this work, a stereocomplex (SC) crystallites cross-linking method was developed to prepare the graphene nanoplatelets (GNPs) filled cellulose nanofibers (CNFs) composite films. The SC crystallites formed between adjacent GNPs exhibit the physical crosslinking effect, which not only prevents the transmission of electron while maintaining the heat diffusion ability in plane but also intensifies the interaction between GNPs to form the integrated GNP network in the whole composite films, endowing the composite films with excellent strength and toughness. As a consequence, the composite films with nacre-like structure exhibit high in-plane thermal conductivity (9.36 W m−1K−1) and high electrical insulation (3.1 × 109 Ω m) with extremely high stability during the repeated bending and heating/cooling measurements. Furthermore, the composite film containing 5 wt% filler exhibits an excellent tensile strength of 111.8 ± 6.1 MPa and high toughness of 24.5 ± 2.0 MJ m−3, which are 51.1% and 75.0% higher than those of the pure CNFs film, respectively. This work provides a valuable strategy for the fabrication of the CNFs-based composite films with promising properties that have great potential as the next-generation thermal management materials.

‘ Rigid‐soft ’ synergistic effects to improve the microstructure and superflexibility properties of aramid nanofiber aerogel

Designing aramid nanofiber (ANF) aerogel with excellent microstructure and high thermal insulation property is benefit for applications in integrated thermal management system. To obtain a structurally controllable ANF-based aerogel, the cellulose nanofiber (CNF) and poly (vinyl alcohol) (PVA) were ‘stiff–soft’ synergistic to improve the microstructure. The cobweb like structures distributed in the honeycomb layered pores of the CNF/PVA/ANF composite aerogel which was conducive to the performance and application of composite aerogel. The resulting CNF1/PVA1/ANF composite aerogels are highly porous (99.12%) and tiny volume shrinkage (4.65%), leading to excellent thermal insulation performance (26.83 mW/m·K). The ‘stiff–soft’ feature endows the composite aerogels high flexibility as well as large compression strength. These favorable multi-features make the CNF/PVA/ANF composite aerogels ideal advanced material for aerospace, industrial, and commercial applications.

Veterinary and sanitary examination of deer milk of the Republic of Sakha (Yakutia)

Reindeer husbandry is one of the main branches of animal husbandry in the north of the Russian Federation. Reindeer products offer dietary, biologically complete meat; high-quality milk; leather and fur raw materials with high thermal insulation properties; antlers contain biologically active substances, endocrine-enzyme and special raw materials. Also the use of reindeers as transport mode ensures the survival of small peoples in extreme living conditions. She-reindeer milk represents a sensitive multicomponent balanced system with high nutritional, immunological and bactericidal properties. The purpose of our work was to conduct a veterinary and sanitary examination of 20 samples of deer milk from Anabar and Neryungri districts of the Republic of Sakha (Yakutia). Organoleptic, physico-chemical and microbiological studies were carried out. Organoleptic studies were conducted according to the technical specifications TU-9861-015-00670203-2007 "Frozen reindeer milk - raw materials" and "TU-9861-014-00670203-2007 "Natural deer milk - raw." Physico-chemical studies were conducted according to the TU-9861-015-00670203-2007 "Frozen reindeer milk - raw materials" and TU-9861-014-00670203-2007 "Natural deer milk - raw." According to organoleptic indicators, samples of deer milk (Anabar district), (Neryungrinsky district) corresponded to the indicators of normative and technical documentation. According to the results of physico-chemical studies, it was established that all samples comply with regulatory and technical documentation. Concerning milk samples from the Anabar district, the fat content was found to be 0.7% higher than in deer milk samples from the Neryungri district. According to the results of microbiological studies, all samples corresponded to the regulatory and technical documentation. According to the results of comparative studies of samples, it was found that all samples had the best taste qualities and meet the requirements of technical specifications. After processing, deer milk can be used in the pharmaceutical, cosmetic and food industries. After ingestion by leaven micro-organisms with sugar and wild berries, deer milk can be used for the production of sour milk beverages for direct consumption, as well as for curd, sour cream and cheese. Deer milk is a unique dairy product that must comply with the biological safety.