Engineering Plastic Characteristics
How to classify plastics?
Roughly divided into two categories:
1. Thermoplastic：It can be formed by flowing into the mold after heating. The resin molecular chains in thermoplastics are linear or branched, and there is no chemical bond between the molecular chains. It softens and becomes plastic after heating, and hardens after cooling. Thermoplastics will soften after reheating. Using heating and cooling can produce a reversible physical change between liquid and solid.
2. Thermosetting plastic：It can soften and flow when heated for the first time, and when heated to a certain temperature, it will generate a chemical reaction, crosslinking, and become a three-dimensional structure, while curing and hardening, this change is irreversible. Reheating can no longer soften and flow. With this characteristic, the plasticizing flow during the first heating is used to fill the mold cavity under pressure, and then solidify into the product of a certain shape and size.
1. Thermoplastic：It can be formed by flowing into the mold after heating. The resin molecular chains in thermoplastics are linear or branched, and there is no chemical bond between the molecular chains. It softens and becomes plastic after heating, and hardens after cooling. Thermoplastics will soften after reheating. Using heating and cooling can produce a reversible physical change between liquid and solid.
2. Thermosetting plastic：It can soften and flow when heated for the first time, and when heated to a certain temperature, it will generate a chemical reaction, crosslinking, and become a three-dimensional structure, while curing and hardening, this change is irreversible. Reheating can no longer soften and flow. With this characteristic, the plasticizing flow during the first heating is used to fill the mold cavity under pressure, and then solidify into the product of a certain shape and size.
What is the definition of engineering plastics?
Engineering plastics generally refer to plastic materials that have at least one of the following conditions:
1. High mechanical strength and proper balance. It means that all mechanical properties can reach a certain level, such as high tensile strength, bending strength, impact strength and high continuous use temperature. The long-term use temperature is above 100°C, and can maintain a long service life. It is suitable for machinery, electrical, automobile, industrial products or structural products.
2. Engineering plastics are also divided into general engineering plastics and special engineering plastics. General engineering plastics have the following conditions：
(1) The price is not very expensive.
(2) Excellent processability, no special processing methods are required.
(3) High production and high consumption.
1. High mechanical strength and proper balance. It means that all mechanical properties can reach a certain level, such as high tensile strength, bending strength, impact strength and high continuous use temperature. The long-term use temperature is above 100°C, and can maintain a long service life. It is suitable for machinery, electrical, automobile, industrial products or structural products.
2. Engineering plastics are also divided into general engineering plastics and special engineering plastics. General engineering plastics have the following conditions：
(1) The price is not very expensive.
(2) Excellent processability, no special processing methods are required.
(3) High production and high consumption.
What is the difference between crystalline and amorphous plastics?
Crystalline plastics refer to the plastics that have regular arrangement of macromolecules inside with a clear melting point. Regularly arranged regions are called crystal regions, and disorderly arranged regions are called amorphous regions. The percentage of crystal regions is called crystallinity. Generally, polymers with crystallinity above 80% are called crystalline plastics.
1. Common crystalline plastics are：
Polyethylene PE, polypropylene PP, polyamide PA6 (Nylon 6), polyamide PA66 (Nylon 66), polybutylene terephthalate PBT, polyethylene terephthalate PET, Polyoxymethylene POM, etc.
2. Common non-crystalline plastics are：
Polystyrene PS, ABS resin, polyacrylic resin PMMA, polycarbonate PC, modified polyphenylene ether PPE, etc.
3. Comparison of properties of crystalline and non-crystalline thermoplastic engineering plastics:
1. Common crystalline plastics are：
Polyethylene PE, polypropylene PP, polyamide PA6 (Nylon 6), polyamide PA66 (Nylon 66), polybutylene terephthalate PBT, polyethylene terephthalate PET, Polyoxymethylene POM, etc.
2. Common non-crystalline plastics are：
Polystyrene PS, ABS resin, polyacrylic resin PMMA, polycarbonate PC, modified polyphenylene ether PPE, etc.
3. Comparison of properties of crystalline and non-crystalline thermoplastic engineering plastics:
| Characteristic | Crystalline Plastics | Amorphous Plastics |
|---|---|---|
| Transparency | Better | |
| Chemical Resistance | Better | |
| Toughness | Better | |
| Wear Resistance | Better | |
| Fluidity | Better | |
| Dimensional Stability | Better | |
| Brittleness | Brittler | |
| Warpage | Larger | |
| Shrinkage | Larger | |
| Colorability | Easier | |
| Hardness | Higher | |
| Heat Resistance | Higher |
Engineering plastics certification and inspection
Many specifications of Nanya engineering plastic have been certified by the Underwriter Laboratories Inc.(UL). What are the main certification items?
The UL NO. of Nanya is E130155 (Taiwan Hsinkang Factory) and E235269 (Guangdong Huizhou Factory). The main items of certification are:
1. Flame resistance: Since most plastics will ignite when exposed to fire, UL and IEC have different levels of flame resistance to meet the requirements of components for different purposes. For example, according to UL-94 regulations, the flame resistance levels of plastics have HB, V-2, V-1, and V-0 specifications from low to high.
2. RTI (Relative Temperature Index): It refers to the highest working temperature of the material. At this temperature, various key properties of the material will not be unacceptably affected due to chemical thermal degradation. Compared to a reference material with confirmed and acceptable corresponding performances, we can define RTI. This index spans the reasonable service life of electrical products.
3. CTI: It is a quality item for single-sided substrate boards used in general household appliances or other high-voltage (110V, 220V) electrical appliances. It is to simulate the situation that the completed circuit board is polluted in the use environment, causing leakage and short circuit at the circuit board space, and also heating and burning. The withstand voltage levels are divided into 0, 1, 2, 3, 4, and 5 levels (100V～600V).
4. Outdoor suitability: The polymer materials considered suitable for outdoor use are tested in accordance with UL 746C. It evaluates polymer material used for electrical equipment. The items are as follows: 1,000 hours of xenon arc aging test, immersed in water at 70 degrees Celsius for seven days.
Before and after the material is exposed to these conditions, the material is tested for flammability, mechanical impact, and changes in mechanical strength. The test may lead to one of the following results:
(f1)—It indicates that the material has met the UV and water exposure or water immersion requirements specified in UL 746C. The material is suitable for outdoor use.
(f2)—It indicates that the material only meets UV or water exposure or water immersion requirements, or has been partially tested according to these requirements.
1. Flame resistance: Since most plastics will ignite when exposed to fire, UL and IEC have different levels of flame resistance to meet the requirements of components for different purposes. For example, according to UL-94 regulations, the flame resistance levels of plastics have HB, V-2, V-1, and V-0 specifications from low to high.
2. RTI (Relative Temperature Index): It refers to the highest working temperature of the material. At this temperature, various key properties of the material will not be unacceptably affected due to chemical thermal degradation. Compared to a reference material with confirmed and acceptable corresponding performances, we can define RTI. This index spans the reasonable service life of electrical products.
3. CTI: It is a quality item for single-sided substrate boards used in general household appliances or other high-voltage (110V, 220V) electrical appliances. It is to simulate the situation that the completed circuit board is polluted in the use environment, causing leakage and short circuit at the circuit board space, and also heating and burning. The withstand voltage levels are divided into 0, 1, 2, 3, 4, and 5 levels (100V～600V).
4. Outdoor suitability: The polymer materials considered suitable for outdoor use are tested in accordance with UL 746C. It evaluates polymer material used for electrical equipment. The items are as follows: 1,000 hours of xenon arc aging test, immersed in water at 70 degrees Celsius for seven days.
Before and after the material is exposed to these conditions, the material is tested for flammability, mechanical impact, and changes in mechanical strength. The test may lead to one of the following results:
(f1)—It indicates that the material has met the UV and water exposure or water immersion requirements specified in UL 746C. The material is suitable for outdoor use.
(f2)—It indicates that the material only meets UV or water exposure or water immersion requirements, or has been partially tested according to these requirements.
Engineering Plastics Trading and Development
I have product development needs. What kind of engineering plastic materials should I choose? Can your company provide assistance?
Nanya engineering plastics have complete specifications and are suitable for a variety of industrial products. You can download our company's catalog for reference. In addition, we can do customized development according to customer requirements. You can make a phone call or email, or leave a message, our professional staff will assist you.
Can free samples of engineering plastic be provided in the initial evaluation? How many quantities can be provided?
After preliminary understanding of the customer's product requirements, we will recommend suitable existing specifications. If there are no suitable specifications, we can also conduct formula adjustment and development. Free samples can be provided for customers to confirm the molding ability and various physical properties. The quantity is determined by the size of the customer's product and the number of trial molds. Generally, the range is from a few kilograms to 50 kilograms. Special cases can be processed individually.
Can technical services be provided if necessary during the trial phase?
Yes, we can assign technical staffs to work with your company to test samples, review results, provide suggestions for improvement, and adjust formulas.
Is there a minimum order quantity? How long is the lead time?
Generally, the minimum order quantity is 1 ton, and if you need color matching (except black), the minimum order is 2 tons; it is make-to-order, and the delivery time ranges from 2 to 4 weeks. Some specifications are in stock and the delivery time can be shortened. If the required quantity is small or the delivery time is urgent, or we have no stock, we can also assist you to purchase from our distributors.