Release time: 2020-02-08 05:06:06
Diphenylmethane diisocyanate is a major downstream product of aromatic hydrocarbons, and is widely used in the production of polyurethane elastomers, synthetic fibers, artificial leather, and solvent-free coatings.
Pure MDI is white to slightly yellow crystals at normal temperature, storage temperature is below 5 degrees, the shelf life is three months, and the packaging is usually a 250 kg iron drum filled with nitrogen (the tank car is filled with nitrogen for a 10-day shelf life).
There are many types of polyurethane floor paints, and the classification methods are also diverse. According to the type of packaging, they are divided into: single cans (single component), double cans (two component), three cans (three component); The dispersion medium or its form is divided into: solvent-based, solvent-free, high-solid, water-dispersed and powder coatings; according to the curing method of the coating, it can be divided into: room temperature curing (that is, self-drying) and heat curing (that is, drying) Grilled) two categories. According to the composition and film formation mechanism of polyurethane floor paint, polyurethane floor paint is divided into five categories: urethane modified oil paint (single component), moisture curing polyurethane coating (single component), and closed polyurethane coating (single component). Component), catalytic curing polyurethane coating (two-component), hydroxyl curing polyurethane coating (two-component). Water-based polyurethane floor paint refers to a coating formed by dissolving or dispersing polyurethane in water. According to its shape and particle size, it can be divided into three categories: polyurethane aqueous floor coatings and polyurethane emulsion floor coatings.
PU sandwich polyurethane composite board has a beautiful appearance and good overall effect. It integrates load bearing, heat preservation, fire prevention and waterproofing, and does not require secondary decoration. It is fast and convenient to install, has a short construction cycle and good comprehensive benefits. This product has a good cost performance advantage, it is a versatile and highly potential energy-efficient building envelope, and it is also a new type of energy-saving sheet promoted and promoted by the Ministry of Construction. Low thermal conductivity is also a highlight of the product. Polyurethane Pu sandwich composite board has a small thermal conductivity and good thermal insulation performance, which is currently the best thermal insulation material.
The materials of general casters are nylon, rubber, elastic rubber, plastic, polyurethane and so on. Polyurethane casters can meet the needs of transportation whether it is operated indoors or outdoors. Elastic glue is more commonly used for floors such as hotels, wooden floors and tiles. Nylon and iron wheels are more suitable for places with uneven or iron filings.
The polyurethane market is mainly spread in developed countries in Europe and the United States. The Asia-Pacific region is mainly represented by China, Japan, and South Korea. These countries and regions account for 90% of the global polyurethane market, and China ’s total polyurethane consumption accounts for half of the world ’s total.
Two-component raw materials used in polyurethane foam, one component is polyisocyanate (commonly known as black material), and the other component is a homogeneous mixture composed of polyether, foaming agent and various other additives (commonly known as white material, also known as white material, also known as Combination polyether).
Polyurethane adhesives mainly include single-component moisture-curing polyurethane sealants for windshield assembly; structural adhesives for bonding glass fiber reinforced plastics and sheet molding composite materials; two-component polyurethane adhesives for interior parts; and water-based polyurethane adhesives. Automotive interior parts are also an area where adhesive usage is increasing. Waterborne polyurethane adhesives widely used in automobiles refer to adhesives formed by dissolving or dispersing polyurethane in water. Most water-based polyurethanes are linear thermoplastic polyurethanes. Because the coating film is not cross-linked and the molecular weight is low, properties such as water resistance, solvent resistance, and film strength are still poor. It must be modified to improve its performance. . The polyester and acrylic hybrids and dispersions are combined with uretdione and isocyanurate to prepare automotive repair varnishes that do not require high-speed stirring equipment, are easy to mix together, and have good adhesion properties.