Urea-formaldehyde plastic is commonly known as “electric jade”. Plastic made with urea-formaldehyde resin as its basic component. It is a thermosetting plastic. There are mainly four types of urea-formaldehyde molding compounds, urea-formaldehyde foam plastics, cast urea-formaldehyde plastics and laminated urea-formaldehyde plastic sheets. Its surface is smooth, hard, bright in color, arc and flame resistant, and has good electrical insulation properties. It is widely used in the manufacture of daily appliances, mechanical parts, accessories for the electrical and instrument industries, various handles and decorations, cultural and educational supplies, various buttons and bottle caps, etc. Urea-formaldehyde foam is mainly used to manufacture sound insulation and heat insulation materials for vehicles, ships, buildings, etc.
Chemical properties
Urea-formaldehyde plastic is a thermoset plastic developed in the 1930s. It is a hard translucent material with coloring properties that is widely used in bottle caps and cosmetic boxes. Urea-formaldehyde plastic products are more expensive than some thermoplastics. But heat resistance and other excellent properties can compensate for the price factor. Because of its translucency, it produces a light and dark color similar to opal glass, so it can produce a variety of beautiful colors. Urea-formaldehyde plastic is the abbreviation of urea-formaldehyde plastic, which reflects the two main raw materials used in the manufacture of this plastic. When an alkaline catalyst is present, these two substances react NH 2 -CO-NH2+HCHO, A monomer is formed, NH2-CO-NH-CH2OH, which when combined with a latent catalyst and heated in the mold creates an acid that promotes polymerization.
Characteristic
Urea-formaldehyde plastic is suitable for coloring in various colors, and can be colored into various shades of colors such as pink and lavender, but the color levels of yellow and orange are less. It is difficult to have a good color contrast, and these colors will fade over time. In the past, the U.S. Department of Commerce has set standards for the color of urea-formaldehyde as a standard for molded urea-formaldehyde plastics, which is known as “Map color”. Urea-formaldehyde is a hard, brittle, odorless and tasteless material. It has good luster and pleasant translucence. It does not generate static electricity and is not easy to absorb dust.
Performance
Compared to phenolic plastics, urea-formaldehyde plastics are much more expensive but have a much wider coloring range. If appearance is important, you will definitely choose urea-formaldehyde. Because urea-formaldehyde is a thermosetting plastic, it can withstand high temperatures without softening, but it will carbonize at around 390℉. In very humid conditions it will absorb water, but this is not a serious drawback. Urea-formaldehyde does not interact with any organic solvents, but it is not resistant to alkali and strong acid, and has excellent resistance to any oil and grease. Although urea-formaldehyde can withstand high temperatures, it cannot be sterilized by steam. In addition to the shrinkage it will produce in the mold, the release shield will also produce a shrinkage of 0.1003 in./in.
Workmanship and price
Because adenal is a thermosetting resin, its processing is limited to die-cast molding, injection molding or extrusion molding. Cold spots in the mold will cause warping, as will too much moisture in the resin. Other disadvantages are streaks at the weld. Due to insufficient ripening, over-ripening or containing gas, bubbles will be generated. If the fluidity is poor in the mold, the surface will produce an “orange peel” look. Among thermoset plastics, urea-formaldehyde is priced in the mid-range, at 65 cents per pound and 3.5 cents per cubic inch per unit volume. The price is significantly higher than phenolic but not as expensive as melamine. Its price is equivalent to resins such as propylene in thermoplastics.
Applications
Urea formaldehyde plastic, as a high-strength, tear resistant, and wear-resistant polymer material, has the characteristics of smooth surface, hardness, bright color, arc resistance, flame resistance, and good electrical insulation performance. Its application fields are very wide, including:
Household appliances: Urea formaldehyde plastic is widely used in the manufacturing of casings, accessories, etc. for household appliances due to its excellent insulation performance and beautiful appearance. For example, electrical switches, sockets, lampshades, and other components are often made of urea formaldehyde plastic.
Mechanical parts: Due to the mechanical strength and hardness of urea formaldehyde plastic, as well as its resistance to deformation, it is often used to manufacture mechanical parts such as gears and bearings.
Electrical and instrumentation industry accessories: In the electrical and instrumentation industry, urea formaldehyde plastic can be used to make various insulation components and decorative parts, such as coil frames, insulation boards, etc.
Handle and Decoration: Urea formaldehyde plastic is brightly colored, odorless and tasteless, suitable for making various handles and decorations, such as toothbrush handles, combs, jewelry boxes, etc.
Cultural and educational supplies: In the field of cultural and educational supplies, urea formaldehyde plastic can be used to make pen holders, stationery boxes, bookshelves, etc., providing convenience for learning and office work.
Bottle caps and packaging boxes: Urea formaldehyde plastic has strong coloring power and bright colors, so it is often used to make packaging materials such as bottle caps and packaging boxes. However, it should be noted that due to the toxicity of formaldehyde, it is not suitable for use in food packaging.
Sound insulation and heat insulation materials: Urea formaldehyde foam plastic is a kind of buffer packaging material with light quality, low price, good heat preservation and corrosion resistance, which is widely used in sound insulation and heat insulation of vehicles, ships, buildings and other fields.
In addition, urea formaldehyde plastic can also be used to manufacture various electronic components, daily necessities, etc. With the continuous advancement of technology and the increasing demand for environmental protection, the application fields of urea formaldehyde plastics will continue to expand.
Overall, urea formaldehyde plastics play an important role in industrial production due to their excellent performance and wide range of applications. At the same time, attention should also be paid to the toxicity of its raw material formaldehyde to ensure compliance with relevant environmental and safety standards during use.
