POM Polyplastics DURACON M90‑44

POM Polyplastics DURACON® M90‑44 (Japan Polyplastics)

POM Polyplastics M90‑44 is a general‑purpose standard‑grade polyoxymethylene copolymer material with well‑balanced overall performance. It is renowned for excellent mechanical properties, wear resistance and dimensional stability. It is especially suitable for applications requiring good wear resistance, high rigidity, stable dimensional performance and chemical resistance.

Main Applications

Automotive industry: automotive components such as fuel‑tank caps, fuel pumps, seat‑belt parts and automotive interior articles. Electrical & electronic: movement gears, structural parts and transmission components for OA equipment such as printers and copiers; AV devices such as DVD / Blu‑ray players; gears and bearings for household appliances such as washing‑machines, refrigerators and electric shavers. Precision‑machinery parts: ideal for manufacturing various mechanical structural components with high‑precision, high‑wear‑resistance and low‑friction requirements, such as gears, bearings, cams and screws. Consumer & industrial goods: residential‑sector articles including zippers, buttons, window‑frame and shutter components; toys and sports‑equipment parts. Other fields: also applicable to valves and other scenarios requiring chemical‑resistance and fuel‑resistance.

Physical‑Mechanical‑Thermal‑Electrical‑Tribological Properties

Property Category	Item	Test Standard (Values may vary across different sources)	Value / Range	Unit
Physical Properties	Density	ASTM D‑792, ISO 1183	1.41	g/cm³
	Water absorption (23℃, 24h)	ASTM D‑570, ISO 62	0.22‑0.50	%
	MFR (190℃ / 2.16 kg)	ASTM D‑1238, ISO 1133	9.0	g/10 min
	Dynamic friction coefficient (against steel)	ASTM D‑1894	0.15‑0.37	—
	Dynamic friction coefficient (against POM)	ASTM D‑1894	0.35‑0.46	—
Mechanical Properties	Tensile strength	ASTM D‑638, ISO 527‑2	60‑62	MPa
	Elongation at break	ASTM D‑638, ISO 527‑2	35‑60	%
	Tensile modulus	ISO 527‑2	2700‑2800	MPa
	Flexural strength	ASTM D‑790, ISO 178	87‑96	MPa
	Flexural modulus	ASTM D‑790, ISO 178	2500‑2580	MPa
	Izod notched impact strength (23℃)	ASTM D‑256	53‑63	J/m
	Izod un‑notched impact strength (23℃)	ASTM D‑256	760	J/m
	Charpy notched impact strength (23℃)	ISO 179/1eA	5.3‑6.0	kJ/m²
	Rockwell hardness (M scale)	ASTM D‑785, ISO 2039‑2	80	—
Thermal Properties	Heat deflection temperature (1.8 MPa, unannealed)	ISO 75‑2/A	95.0	°C
	Heat deflection temperature (1.32 MPa)	ASTM D‑648	110	°C
	Coefficient of linear thermal expansion (flow / cross‑flow, 23‑55°C)	ASTM D‑696, ISO 11359‑2	10‑12 (1.2E‑4)	×10⁻⁵/°C or cm/cm/°C
Electrical Properties	Volume resistivity	ASTM D‑257, IEC 60093	1 × 10¹⁴	Ω·cm
	Surface resistivity	ASTM D‑257, IEC 60093	1 × 10¹⁶	Ω
	Dielectric strength (2 mm or 3 mm)	ASTM D‑149, IEC 60243‑1	19‑24	kV/mm or MV/m
Flammability	UL94 rating	UL 94	HB	—
	Molding shrinkage	—	1.9‑2.5	%

Injection‑Molding Parameters

Process Stage	Parameter	Recommended Range	Unit	Remarks
Pre‑drying	Drying temperature	80‑90	°C	Drying is recommended. Despite low moisture absorption, drying improves dimensional stability and surface appearance.
	Drying time	3.0‑4.0	hr
	Residual moisture content	< 0.1‑0.2	%
Barrel temperature	Rear‑zone temperature	170‑190	°C	POM has a narrow processing window. Temperatures above 220 °C are strictly prohibited; otherwise formaldehyde gas will be generated through thermal decomposition.
	Middle‑zone temperature	180‑200	°C
	Front‑zone temperature	185‑210	°C
	Nozzle temperature	180‑210	°C	Slightly lower than or close to front‑zone temperature.
	Melt temperature	190‑210	°C
	Mold temperature	60‑80 (can be increased up to 80‑105)	°C	Higher mold‑temperature (e.g. 80‑105 °C) promotes crystallization integrity, improves dimensional stability, surface gloss and reduces sink‑marks.
Injection parameters	Injection pressure	49‑98 (or 40‑130)	MPa	Higher value for thin‑wall parts; lower value for thick‑wall parts.
	Hold‑up pressure	Comparable to or slightly lower than injection pressure (50‑150)	MPa	Relatively high hold‑up pressure is required to reduce pressure drop and prevent part shrinkage.
	Back pressure	0.5‑3.0	MPa	Maintain low back‑pressure.
	Injection speed	Medium‑to‑high (5‑50 mm/s)	—	Recommended strategy: medium pressure, medium speed, moderate‑low melt‑temperature and relatively high mold‑temperature.
	Screw speed	100‑150	rpm	Avoid excessive screw speed; keep cushion residual minimal.
Post‑treatment	—	—	—	Generally unnecessary. Conditioning or annealing treatment can be applied for high‑precision parts to release internal‑stress.
	Barrel residence time	＜20	min	Avoid long‑term high‑temperature retention.
Shutdown procedure	Short‑term stop	Cool barrel below 150	°C	Long‑term shutdown purge barrel with PE / PP.

Note: All data for reference only, subject to official TDS and COA.