POM Baotailin Nantong F20‑02

POM Baotailin Nantong F20‑02 is a medium‑viscosity, high‑strength, high‑rigidity general‑purpose injection‑molding polyoxymethylene copolymer. Featuring balanced mechanical performance, good wear resistance and dimensional stability, it is widely adopted in multiple industrial fields.

Main Applications

Automotive industry: automotive pumps, carburetor components, fuel hoses, power valves, universal‑joint bearings, motor gears, crankshafts, handles, instrument panels, automotive window‑lift assemblies, electrical switches, seat‑belt buckles and other auto accessories. Industrial components: wear‑resistant and self‑lubricating engineering parts such as gears, bearings, cams, sliders, pump housings and valves. Electrical‑electronic: electrical components, connectors, housings, switches. Home appliances: household‑appliance parts including washing‑machine gears and coffee‑machine components. Others: precision mechanical parts, toys, zippers.

Physical‑Mechanical‑Thermal‑Electrical‑Tribological Properties

Property Category	Item	Test Standard	Test Data	Unit
Physical Properties	Density	ASTM D792	1.41	g/cm³
	MFR (190 °C / 2.16 kg)	ASTM D1238	8.9‑9.0	g/10min
	Water absorption	—	approx. 0.2‑0.5	%
Mechanical Properties	Tensile strength (yield)	ASTM D638	59.4	MPa
	Elongation at break	ASTM D638	32.8	%
	Tensile modulus	ASTM D638	2560	MPa
	Flexural strength	ASTM D790	89.2	MPa
	Flexural modulus	ASTM D790	approx. 2400‑2700	MPa
	Izod notched impact strength (23 °C)	ASTM D256	6.1	kJ/m²
	Rockwell hardness (M Scale)	—	approx. M75‑80	—
Thermal Properties	HDT @1.8 MPa	ASTM D648	95.3	°C
	Melting point	—	approx. 162‑173	°C
Flammability	UL94 rating (1.5 mm)	UL 94	HB	—

Injection‑Molding Parameters

Parameter	Typical Value / Range	Remarks & Instructions
Drying Treatment		Although POM has low moisture absorption (approx. 0.2‑0.5 %), drying is recommended. Moisture at high temperature causes degradation, bubbles and silver streaks; drying also improves dimensional stability.
Drying temperature	80‑100 °C	Dehumidifying dryer is recommended. Material bed thickness ≤30 mm.
Drying time	2‑4 h	Ensure sufficiently low moisture content (normally ＜0.2 %).
Barrel Temperature		POM has a narrow processing temperature window. Temperature shall never exceed 220 °C; otherwise irritating formaldehyde gas will be generated. Material residence time in barrel shall not exceed 20 minutes.
Rear zone (feed zone)	150‑170 °C	Near feed throat; avoid over‑temperature to prevent bridging.
Middle zone (compression zone)	170‑190 °C	Main plasticizing zone; keep uniform temperature.
Front zone (metering zone)	180‑200 °C	Close to nozzle; excessive temperature causes POM degradation.
Nozzle temperature	170‑190 °C	Normally slightly lower than front‑zone temperature to prevent drooling; raise moderately in case of blockage.
Melt temperature	~180‑205 °C	Must not exceed 220 °C. Avoid high temperature and long residence time to prevent POM degradation (decomposition temperature approx. 220‑240 °C).
Mold temperature	40‑80 °C (or 60‑80 °C)	High mold temperature (80‑100 °C): uniform crystallization and good toughness, yet longer cooling cycle. Low mold temperature (40‑60 °C): poor surface gloss and high residual stress. Take anti‑burn precautions for hot ejected parts.
Injection pressure	80‑150 MPa	Adjust according to wall thickness and fluidity; 120‑150 MPa for thin‑wall parts, 80‑120 MPa for thick‑wall parts. Relatively high hold‑up pressure (comparable to injection pressure) is required to reduce pressure drop.
Injection speed	Medium‑to‑high (30‑80 mm/s)	Too‑fast speed causes turbulence and burning; too‑slow speed leads to short shots and prominent weld lines. Multi‑stage speed control is suggested: low speed for runner filling, medium‑high speed for cavity filling.
Hold‑up pressure	50‑70 % of injection pressure	Compensates POM shrinkage, reduces sink marks and dimensional deviation.
Hold‑up time	5‑15 s	Adjust according to part wall thickness.
Back pressure	0.5‑2.0 MPa	Low back‑pressure improves melt homogeneity and degassing; excessive back‑pressure causes overheating and degradation.
Screw speed	30‑80 rpm	Avoid excessive rotational speed to prevent shear‑heat‑induced degradation. Keep cushion volume low.
Cooling time	10‑30 s	Adjust according to part thickness and mold temperature to ensure full cooling and anti‑deformation upon ejection.

Note: All data above is for reference only.