POM performance parameter Performance index homopolymer POM copolymerization POM 25%GFPOM relative density One point four three One point four one One point six one Water absorption rate,% Two point five Two point one - Molding shrinkage rate,% 1.5 ~ 3 1.5 ~ 3.5 - Tensile strength, MPa Seventy Sixty-two One hundred and thirty Elongation at break,% Forty Sixty - Bending strength, MPa Ninety Ninety-eight One hundred and eighty-two Tensile modulus of elasticity, MPa Three thousand one hundred and sixty Two thousand eight hundred and thirty Eight thousand and three hundred Flexural modulus of elasticity, MPa Two thousand eight hundred and eighty Two thousand and six hundred Seven thousand and six hundred Compression strength, MPa One hundred and twenty-seven One hundred and ten - Shear strength, MPa Sixty-seven Fifty-four - Notch impact strength, (J/m) Seventy-six Sixty-five Eighty-six Rockwell hardness M94 M80 - Friction factor - Zero point one five - Fatigue limit, MPa Thirty-five Thirty-one - Thermal deformation temperature (1.82MPa), centigrade One hundred and ten One hundred and twenty-four One hundred and sixty-three Long term use temperature, centigrade Eighty One hundred - Coefficient of linear expansion (x 10K) Seven point five Eight point five Two point six Thermal conductivity [W/ (m ? K)] Zero point two three Zero point two three - Volume resistivity, Omega cm Ten Ten 3.8 x 10 Dielectric constant (10Hz) Three point eight Two point seven PPO L) non crystalline material, moisture absorption is small, the PPO water absorption rate is very low, but the water will make the product appear on the surface of silver, bubbles and other defects, therefore, can be placed in the oven raw 80~1OOC Shen, dry 1-2h after use. 2) the molecular bond of PPO is very rigid, and the glass conversion temperature is high, and it is not easy to orientate, but it is difficult to relax after forced orientation. Therefore, the residual internal stress in the product is high, and it should be treated after the post. 3) PPO is an amorphous material. The rheological properties of the material in the melting state are close to the Newton fluid, but the greater the degree of deviation from the Newton fluid as the temperature rises. 4) the viscosity of PPO melt is large, so the temperature should be improved and the injection pressure should be improved to improve the filling ability. 5) the reuse of PPO can be reused, and it is used repeatedly 3 times, and its performance is not significantly reduced. 6) the PPO melt should be molded by a screw injection molding machine. The nozzle has a good straight through, and the aperture is 3-6mm 7) in PPO injection molding, high pressure and high speed injection should be taken, and the time of pressure protection and cooling should not be too long. 8) the sprue mold should adopt large taper?or?by pulling hook, sprue to stub as well. 9) the gate should be directly, fanned?or?flat, and the diameter should be increased properly when the needle gate is used, and the structure of the hot runner can be used for the long cast. 10) the forming shrinkage rate of PPO is small, which is generally 0.2% 1 0.7%, so the product has good size stability. 11) poor fluidity, which is similar to Newton fluid, the viscosity is more sensitive to the temperature, and the thickness of the product is generally above 0.8 mm. It is very easy to decompose, and the corrosion gas is produced when decomposing. The molding temperature should be strictly controlled. The mold should be heated and the flow resistance of the feed system should be small. 12) water polyphenylene ether's low rate of about 0.06%, but the trace moisture can lead to smooth silver and other phenomena appear on the surface of the product, it is best for the drying process, the temperature can not be higher than 150 degrees, otherwise the color will change. 13) the molding temperature of polyphenylene ether is 280-330 degrees, and the molding temperature of the modified polyphenylene ether is 260-285 degrees. PPO plastic raw material injection process melting temperature: 270-290 C application area