ABS key cap: low price, high plasticity, good surface texture, but not high temperature resistance, easy to deformation, the biggest disadvantage of ABS material is that it is easy to appear oil phenomenon, especially for opponents of oil friends, not version out of a month to ensure the key cap shining right, greasy feel decreased obviously.

PBT key cap: the price is more expensive than ABS, high temperature resistance, wear resistance, not easy to deformation, oil resistance is significantly higher than ABS key cap, processing is more complex than ABS.

POM key cap: expensive, POM key cap wear-resisting degree and hardness is higher than PBT key cap, currently on the market for black, processing injection molding is the most difficult of the three key caps.

Toxic by inhalation.

The application of PMMA is mostly in the fields of, machinery, medical treatment, construction and so on. What can be contacted daily is probably plexigloid, cosmetic bottles and so on. Such use is completely ok, but if you come into contact with PMMA powder, it is better to stay away from it.

FDA The Food and Drug Administration (FDA) is one of the U.S. government's executive agencies within the Department of Health and Human Services (DHHS) and the Department of Public Health (PHS).

As a scientific regulatory agency, FDA's job is to ensure the safety of food, cosmetics, drugs, biologics, medical devices and radiological products manufactured or imported into the United States. It was one of the first federal agencies whose primary function was to protect consumers. The organization is relevant to the lives of every American citizen. Internationally, FDA is recognized as one of the largest food and drug administration agencies in the world. Many other countries seek and receive HELP from the FDA to promote and monitor the safety of their products.

Food and Drug Administration (FDA) supervisor: supervision and inspection of food, drugs (including veterinary drugs), medical devices, food additives, cosmetics, animal food and drugs, wine and beverages with an alcohol content of less than 7%, and electronic products; Testing, inspection and certification of items affecting human health and safety by ionic and non-ionic radiation generated during use or consumption of products. According to regulations, the products must be certified safe by the FDA before they can be sold on the market. FDA has the authority to inspect manufacturers and prosecute offenders. According to the different product ranges regulated, there are several major regulatory agencies as follows:

Center for Food Safety and Practical Nutrition (CFSAN) :

The center has the largest workload at the FDA. It is responsible for food safety throughout the United States, except for meat, poultry and eggs, which are covered by the U.S. Department of Agriculture. Despite having one of the safest food supplies in the world, the United States suffers from approximately 76 million foodborne illnesses, 325,000 hospitalizations and 5,000 deaths each year. The Center for Food Safety and Nutrition works to reduce foodborne illness and promote food safety. And promote various plans, such as: HACCP plan promotion and implementation.

The centre's functions include: ensuring the safety of substances and pigments added to food; Ensure the safety of foods and ingredients developed through bioprocesses; Responsible for the management activities in the proper labeling of food products (e.g. ingredients, nutrition and health claims) and cosmetics; Develop policies and regulations governing dietary supplements, infant food formulations and medical foods; Ensure the safety of cosmetics ingredients and products and ensure the correct identification; Supervise and regulate the after-sale behavior of food industry; Conduct consumer education and behavior development; Partnerships with state and local governments; Harmonize international food standards and safety.

Center for Drug Evaluation and Research (CDER):

The center aims to ensure the safety and effectiveness of prescription and over-the-counter drugs, evaluates new drugs before they are marketed, and monitors the more than 10,000 drugs on the market to ensure that products meet the highest standards that are constantly updated. The center also monitors the authenticity of drug advertisements on television, radio and in publications. Strict supervision of drugs to provide consumers with accurate and safe information.

Center for Equipment Safety and Radiation Protection Health (CDRH):

The center ensures that new medical devices are safe and effective. Because there are more than 20,000 companies around the world that manufacture more than 80,000 types of medical devices, from blood glucose monitors to artificial heart valves. These products are vital to human life, so the center also oversees nationwide after-sales service. The center also sets safety standards for products that produce radiation, such as microwave ovens, television sets and mobile phones.

4. Center for Evaluation and Research of Biological Products (CBER):

The center oversees biological products that can prevent or treat disease, and is therefore more complex than chemical synthetic drugs, including scientific studies of the safety and efficacy of blood, plasma, vaccines and the like.

5. Center for Veterinary Medicine (CVM):

The center monitors animal food and drugs to ensure their usefulness, safety and effectiveness in sustaining life and alleviating suffering.

U.S. federal law requires that imported laser products (such as VCDS and DVDS), microwave and radio-frequency emission products (such as microwave ovens), and products containing X cathode rays (such as televisions) be approved by the FDA.

PP is short for polypropylene, is a colorless, odorless, non-toxic, translucent solid substance. Polypropylene is a kind of thermoplastic synthetic resin with excellent properties, such as chemical resistance, heat resistance, electrical insulation and good high wear-resistant processing properties, which makes polypropylene widely used in machinery, automobile, construction, packaging and many other fields.

We can see all kinds of plastic in our daily life. Different plastics have different uses. We usually just classify plastics according to their hardness and softness. There are disposable plastic bags that are soft, and car parts that are hard. There are many different types in between. Let's take a look at one of these plastics -- ABS plastic.

ABS plastic has its own unique advantages relative to other plastics. In strength, toughness, comprehensive performance and other aspects are relatively high. And ABS plastic is relatively heat resistant, but its liquidity is relatively poor compared with other types of plastic. Comprehensive ABS plastic characteristics, its application is different according to its characteristics, so ABS plastic suitable for what aspects?

ABS plastic is a kind of engineering plastic alloy, now mainly used in electronic products, in a long time, there will be better development in the field of electronics. In addition, in the manufacturing of cars, office and communication equipment and other aspects of the same application. It can also be used in pipelines. It can also be used as the main raw material of washing powder. It is believed that in the future development, the application of ABS will be more extensive.

With the development of science and technology, people understand the performance of ABS more deeply. Through the research and development of experts, the application of ABS plastic will be more broad, but also will find more characteristics. Through modification, it will be used in a wider area. It is applied in practice, developed in application, and applied in development. By now, you have a certain understanding of ABS plastic? Knowing every little detail of life will lead to great gains.

Modified plastics refer to plastic products with improved flame retardancy, strength, impact resistance, toughness and other properties after filling, blending and strengthening on the basis of general plastics and engineering plastics. Ordinary plastic often has its own characteristics and defects, modified plastic is to change the properties of plastic, the basic technology includes:

1. Enhance: blend glass fiber with plastic to increase the mechanical strength of plastic.

2. Filling: mix mineral and other filler with plastic, so that the shrinkage rate, hardness, strength and other properties of plastic are changed.

3. Toughening: by adding toughening agent to the common plastic to improve the toughness of the plastic, toughened modified product: rail gasket.

4 flame retardant: add flame retardant to ordinary plastic resin, plastic can have flame retardant properties, flame retardant can be one or several flame retardant compound system, such as bromine + antimony series, phosphorus series, nitrogen series, silicon series, and other inorganic flame retardant system.

5 cold resistance: increase the strength and toughness of plastic at low temperature, the inherent low temperature brittleness of general plastic at low temperature, so that the application is limited in low temperature environment, need to add some low temperature resistant toughening agent to change the brittleness of plastic at low temperature, such as car bumper and other plastic parts, general requirements for cold resistance.

As the downstream industries with a large demand for modified plastics are mostly consumer industries, with the upgrading of consumption and the start of domestic demand, these industries will grow at a high speed, thus driving the large demand for modified plastics.

With the deep understanding of the plastic products, small make up understanding of modified plastics is also gradually deepened, what is a modified plastics, modified plastics of several common modification methods, answer not to say on the standard, but also can be to the point, but more know small make up more don't understand, why to the production of modified plastics, ordinary plastic is bad? Xiaobian specially consulted the professional customer service staff of Yuanbo plastics. They gave professional advice to xiaobian and told me what is the purpose of producing modified plastics. Next, follow xiaobian to see it.

When we use ordinary plastics, we will also find that ordinary plastics often have its own characteristics and defects. Adding modifiers in products can overcome the defects of poor processing performance and insufficient strength, and give new functions such as flame retardant, weather resistance, high impact resistance, antibacterial and antistatic. For example, the hardness of the plastic raw material nylon PA is not hard enough, so an appropriate amount of glass fiber is added to the original PA plastic to increase the hardness and wear resistance of the product. For example, conductive carbon black is added to ABS plastic to make ABS particles become conductive material. By improving the flame retardant, strength, impact resistance, toughness and other properties of plastic raw materials, the modified plastics can better meet the needs of the market.

There is also a gap in the price of different brands of modified plastics, and users need to weigh the pros and cons when buying. Before buying, consult more manufacturers that have done better, refer to professional advice, can bring you great convenience.

In short, it is still more complex. It is necessary to consider your own needs and consult manufacturers more. Source bo plastic modified plastic variety, it is manufacturers direct sales, the price is relatively affordable, is a good choice oh, still waiting for what, quickly pick up the phone at hand to contact source Bo plastic customer service staff: 020-22361316!

The shrinkage rate of PA66 can not be summarized in a word, nor can it be easily known what the shrinkage rate of PA66 is. Because there are different kinds of PA66, such as flame retardant PA66, glass fiber reinforced PA66, ore filling reinforced PA66, transparent PA66 and so on. Different types of PA66 have different shrinkage rates, and even the same PA66 may have different shrinkage rates.

1. Definition of shrinkage rate

The shrinkage of plastic is the percentage difference between the size of the plastic part at the molding temperature and the size after it is taken out of the mold and cooled to room temperature. It reflects the extent to which the plastic parts are reduced in size after being taken out of the mold and cooled.

2. Factors affecting shrinkage rate

A, mold temperature is high, shrinkage rate increases;

B. The pressure holding time is long, and the shrinkage rate decreases, but the shrinkage rate is not affected after the gate is closed;

C. The melt temperature increases, and the shrinkage rate decreases;

D, molding temperature unchanged, if the injection pressure increases, the product shrinkage rate is reduced

E. As the holding pressure increases, the shrinkage rate decreases;

F. The injection speed is high, the shrinkage rate tends to increase slightly, and the influence is small;

G, the cooling time in the mold is long, the shrinkage rate is reduced;

H. Forming shrinkage is large and shrinkage is reduced. The posterior contraction was stable about a week after the first two days. Plunger injection machine molding shrinkage rate is large.

3. Specifically analyze the shrinkage rate of PA66

When analyzing the shrinkage rate of PA66, the most common glass reinforced PA66 is discussed. Glass reinforced PA66 is PA66 with filling material - glass fiber added. In addition to the above mentioned factors that may affect the shrinkage rate, such as temperature, pressure, injection speed, etc., in addition, glass fiber itself will also affect the shrinkage rate of PA66. After adding glass fiber, the forming shrinkage of PA66 becomes smaller.