万人炸金花

plastic

Release date: 2018-12-11 Views: 416



PVC

● Feature introduction

Polyvinyl chloride, English for short (Polyvinyl chloride), is an initiator of vinyl chloride monomer (VCM) in peroxides, azo compounds, etc .; Polymerized polymer. Vinyl chloride homopolymers and vinyl chloride copolymers are collectively referred to as vinyl chloride resins. PVC is an amorphous white powder with a small degree of branching, a relative density of about 1.4, a glass transition temperature of 77 to 90 ° C, and decomposition at about 170 ° C. Poor stability to light and heat. Above 100 ° C or over a long period of time When exposed to sunlight, it will decompose to produce hydrogen chloride, which will further automatically catalyze decomposition, causing discoloration, and physical and mechanical properties will also rapidly decrease. In practical applications, stabilizers must be added to improve the stability to heat and light.


The molecular weight of industrially produced PVC is generally in the range of 50,000 to 110,000. It has a large polydispersity. The molecular weight increases with the decrease of the polymerization temperature. There is no fixed melting point. The softening begins at 80 to 85 ° C and the viscoelastic state becomes 130 ° C , 160 ~ 180 ℃ began to transition to viscous flow state; has good mechanical properties, tensile strength of about 60MPa, impact strength of 5 ~ 10kJ / m2; has excellent dielectric properties. On October 27, 2017, the list of carcinogens released by the International Agency for Research on Cancer of the World Health Organization has initially compiled the reference. Polyvinyl chloride is in the list of Class 3 carcinogens.


Polyurethane PUR

● Feature introduction

PU / PUR cables have: high abrasion resistance, high tear resistance, good weather resistance, high elasticity, good heat aging performance, excellent water resistance, and microbial resistance. The short-term use temperature can be between 40 ° C and + 120 ° C. Long-term use temperature can reach 90 ° C. Excellent water resistance is an essential performance requirement for cable jackets. Increased temperature increases hydrolysis. The Arrhenius curve of PUR has good hydrolytic stability. 20N / mm2 is the lowest strength requirement generally accepted in the cable industry. The curve will drop to 20 N / mm2 after 20,000 hours of immersion in 72 water. PUR is very resistant to ozone and can meet VDE472-805 requirements. PUR sheath products have excellent resistance to microorganisms. According to D1N57472 (VDE 472-804) standard, the saponification values of polymerase products are lower than 200mgKOH / g, which meets the requirements of VDE 0282-10. Free from microbial attack. PUR cables have excellent resistance to grease. Can be used for spiral cables, towline cables, sensor encoder cables, servo motor cables, shielded control cables and power cables in motion


TPE

● Feature introduction

Generally composed of two materials, mainly composed of a hard nano-domain (Nano-Domain) dispersed in a soft rubber region due to phase separation. This region is mainly composed of molecules with rigid (Rigid) and flexible (Flexbie), and the bond between the two is usually a covalent bond. Therefore, the operating temperature range of TPE is generally between the glass transition temperature (Tg) and the melting point (Tm). Another type of rubber-plastic composite TPO or cross-linked TPO (TPV), the above-mentioned soft region is usually composed of elastic rubber and dispersed in the plastic hard substrate (Matrix). The two regions are different. The composition of the polymer is different from the aforementioned covalent bonding.


TPU

● Feature introduction

Due to the different materials of the soft section, it is divided into Polyeaster Type & Polyether Type. The main differences are that the polyester TPU soft segment is more resistant to non-polar solutions, has better physical properties (tear resistance, high abrasion resistance, toughness), weather resistance, oxidation resistance, oil resistance; and polyether The soft segment is more resistant to hydrolysis, has high anti-mold and anti-bacterial stability, and has a large rebound. Due to low hysteresis, low thermal accumulation and low temperature characteristics. The main key is the relationship between the polyether segments. TPU has better resistance to hydrolysis and elasticity, and can be over-molded with PC, PC / ABS, and ABS (true secondary overmolding). The above two types of materials have excellent biocompatibility, so it is the most widely used of all TPE materials in biomedical applications.

Operating temperature: -70 ~ 100 ° C

Shore: 40A ~ 74D

Specific gravity: 1.1 ~ 1.3

Features: Very good resistance to oil, fuel, grease, general aliphatic compounds, and slightly worse resistance to aromatics. Not resistant to polar organics, such as DMS (Dimethyl Sulphoxide), DMF (Dimethyl Formamide), because this type of solvent will attack the TPU, but it is a very good solvent. TPU is as resistant to water and water as TPEE (but in extremely high and extreme (Except low pH)


TPV

● Feature introduction

Compound 再经过动态硫化而成,具有高度交联橡胶分散相,且有著动态硫化的操作反应下,所以其耐热性较一般未交联之合胶为高,有著较低的介电系数,特别是抗永久变形性质,是所有TPE 中最优者,经过改良之TPV,已可与PA、PC、PC/ABS、ABS 作over-molding(真性二次包覆射出成型) It is made of PP / EPDM Compound through dynamic vulcanization. It has a highly crosslinked rubber dispersed phase and has dynamic vulcanization under the operating reaction. Therefore, its heat resistance is higher than that of general uncrosslinked glues, and it has a lower dielectric strength. The electrical coefficient, especially the resistance to permanent deformation, is the best of all TPEs. After improved TPV, it can be over-molding with PA, PC, PC / ABS, and ABS (true secondary coating injection molding)

Operating temperature: -60 ~ 135 ° C

Shore: 35A ~ 50D

Specific gravity: 0.85 ~ 1.0

Characteristics: Resistance to polar solutions (such as water, aqueous solution, ethanol, etc.), oil resistance, ink resistance, resistance to polar solutions (hydrocarbons, halogen carbides) will swell


XLPE

● Feature introduction

The cross-linked polyethylene insulated cable adopts the method of peroxide cross-linking to change the polyethylene molecule from a linear molecular structure to a three-dimensional network structure and a thermoplastic material to a thermosetting material. Improve the current carrying capacity of the cable. XLPE insulated cable has the following advantages:

1. Heat resistance: XLPE with mesh structure has excellent heat resistance. It does not decompose and carbonize below 300 ℃, long-term working temperature can reach 90 ℃, and thermal life can reach 40 years.

2. Insulation performance: XLPE maintains the original good insulation characteristics of PE, and the insulation resistance is further increased. Its dielectric loss tangent is very small and is not affected by temperature.

3. Mechanical characteristics: Due to the establishment of new chemical bonds between macromolecules, the hardness, stiffness, abrasion resistance and impact resistance of XLPE have been improved, thereby making up for the shortcomings of PE being easily cracked by environmental stress.

4. Chemical resistance: XLPE has strong acid and alkali resistance and oil resistance. Its combustion products are mainly water and carbon dioxide, which has less harm to the environment and meets modern fire safety requirements.






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