The development trend of PU hard foam
After decades of development, polyurethane materials have covered all aspects of production and life, but there is still a vast space for future development.
Rigid foam is the big single application form of polyurethane materials.
In the field of building insulation materials for exterior walls, the proportion of polyurethane rigid foam in China is 7%, while that of the United States is 65%, and there is still a lot of room for improvement. Second, the rapid development of China’s cold chain logistics will bring greater demand for rigid foam.
Refrigeration and freezing equipment for home appliance and food industries
PU rigid foam is the ideal insulation material for freezing and refrigerating equipment, which can achieve a more ideal insulation efficiency.
The use of PU rigid foam as the insulation layer of the refrigerator, freezer, insulation layer thin, under the condition of equal external dimensions, the effective volume is much larger than other materials for insulation layer, and reduce the self-weight of the appliance.
PU rigid foam is also used in the manufacture of portable thermal insulation box, used to transport biological products that need low-temperature storage, pharmaceuticals and food that needs to be insulated and preserved.
Marine fisheries, meat and other food processing industry enterprises such as freezing and refrigerating room, large cold storage also use polyurethane foam as insulation materials, more hard foam metal sandwich panel assembly, convenient and fast.
Industrial equipment and pipeline insulation
Many brewing, chemical, storage and transportation enterprises, there are different heat preservation, cold preservation, etc. PU rigid foam construction is convenient, sanitary, excellent insulation effect, is a good insulation material.
Storage tanks, pipelines are commonly used in industrial production equipment, in oil, natural gas, oil refining, chemical, light industry and other industries are widely used.
PU rigid foam as pipeline insulation materials, commonly used in crude oil pipeline, petrochemical and other industries pipeline insulation, has replaced perlite and other materials with greater water absorption.
City, factory centralized heating project of hot water pipes generally use PU rigid foam as insulation material, requiring long-term resistance to 100 ° C, the main pipeline requires resistance to 130 ° C or even higher temperature, there are some high temperature PU rigid foam products have been developed for such purposes.
Building materials
Housing construction is one of the important applications of PU rigid foam.
The United States and other countries, the construction of PU rigid foam accounted for about half of the total consumption of rigid foam, refrigerators, freezers and other hard foam dosage of more than double.
In our country, hard foam has been promoted and applied to the heat insulation and waterproofing of the roof of residential and office buildings, heat insulation of walls, insulation materials for cold storage, grain storage, etc.
PU hard foam sheet can be made into various folding mobile houses, as temporary, field, with room. Hydraulic facilities such as concrete dams in the cold winter construction need to take insulation measures, can be sprayed on the surface of new concrete PU hard foam as a thermal insulation layer.
Transportation and water materials
PU rigid foam is now widely used in automobile headliner and interior parts, which used to be fabric or PVC film compounded with polyurethane soft foam, and now PU rigid foam material is basically used.
Rigid polyurethane structural foam is used for a variety of automotive parts, such as door panels, luggage compartment covers, engine covers, etc. Elastic polyurethane semi-rigid foam is used as shock absorbing parts of automobiles. Train carriages are insulated with PU rigid foam, and the effect is remarkable.
PU hard foam is also used as insulation material for refrigerated cars, refrigerated containers, etc., which can ensure the temperature of frozen food in the required range during long-distance transportation. It can also be used as insulation material for air-conditioning carriages.
China’s Qingkang Highway and Qinghai-Tibet Railway have adopted rigid polyurethane foam as roadbed insulation material in the permafrost area. The construction methods of rigid polyurethane foam applied on the roadbed include laying sticky board method and on-site spraying method.
Military and aerospace
Polyurethane foam can also be used as the substrate of wave absorbing materials without echo dark room, commonly used in national defense and related research fields.
Polyurethane foam absorbing material can also be used on the fuselage and wings of stealth aircraft, and can be used to build echo-free boxes to cover the reflective objects in the test environment, such as radar antenna bins, antenna mounts, turntables, test stands, etc.
Polyurethane foam is also used as camouflage material for military facilities, which can simulate the natural ground state and achieve the camouflage purpose of “hiding the real and showing the fake”.
PU rigid foam is also used as heat insulation material for aerospace aircraft, etc. PU rigid foam has excellent temperature and cold resistance and adiabatic properties in the temperature range of -45~100℃, which is very suitable for heat insulation material in aerospace industry.
