POM YUNTIANHUA CZAF0101

POM YUNTIANHUA CZAF0101 is high‑flow copolymer acetal (POM‑C) with favorable mechanical properties. It features good wear‑resistance, wide service‑temperature range, excellent dimensional stability and chemical‑resistance.

Main Applications

Electrical & electronic: gears, bearings and structural components for home appliances including washing‑machine, juicer parts, timer assemblies and keyboards. Automotive: skeleton‑type components such as gears, bearings, auto‑parts and instrument inner components. Precision mechanical & industrial parts: high‑precision, wear‑resistant, low‑friction mechanical structural parts, e.g. gears, bearings, cams, screws, levers and pulleys. Consumer & others: toys, sports‑equipment and other daily‑use articles.

Physical Properties

Property Category	Item	Test Standard	Reference Range	Unit
Physical Properties	Density	ISO 1183	1.41‑1.60	g/cm³
	Water absorption (23℃,24h)	ISO 62	0.2‑0.7	%
	MFR (190℃/2.16 kg)	ISO 1133	7.0‑9.0	g/10min
Mechanical Properties	Tensile yield strength (23℃)	ISO 527‑2	50‑110	MPa
	Elongation at break (23℃)	ISO 527‑2	13‑140 (typically 30‑60)	%
	Flexural modulus (23℃)	ISO 178	2000‑2800 (higher for reinforced grades)	MPa
	Charpy notched impact strength (23℃)	ISO 179/1eA	5.0‑7.0	kJ/m²
	Rockwell hardness (M‑Scale)	ISO 2039‑2	~80‑82	—
Thermal Properties	HDT (1.8 MPa)	ISO 75‑2/A	70‑115 (higher for reinforced grades)	℃
Flammability	UL94 rating	UL 94	HB	—

Injection Molding Parameters

Process Stage	Parameter	Recommended Range	Unit	Remarks
Pre‑drying	Drying temperature	80‑90	℃	Drying is recommended for damp raw materials or high‑precision parts to avoid bubbles or silver streaks, despite low moisture absorption.
	Drying time	2‑4	h
Barrel temperature	Rear zone	150‑180	℃	Do not exceed 230 ℃, otherwise formaldehyde gas will be generated by decomposition. Avoid contact with copper which accelerates POM degradation.
	Middle zone	170‑190	℃
	Front zone	180‑200	℃
	Nozzle temperature	180‑200	℃	Slightly lower than or close to front‑zone temperature.
	Melt temperature (POM‑K)	190‑210	℃
	Mold temperature	80‑90 (60‑105)	℃	Higher mold temperature improves crystallization, dimensional stability and surface gloss.
Injection parameters	Injection pressure	80‑130	MPa	Adjust according to part geometry and wall thickness.
	Hold‑up pressure	40‑80 (or 50%‑80% of injection pressure)	MPa	Proper hold‑pressure reduces shrinkage and sink marks.
	Back pressure	0.5‑2.0	MPa	Keep as low as possible; excessive back‑pressure causes thermal‑shear degradation.
	Injection speed	Medium	—	Slow speed causes flow marks; excessive speed induces jetting and shear degradation.
	Screw speed	50‑100	rpm	Avoid high rotational speed to prevent excessive shear heat and material degradation.
	Barrel residence time	As short as possible (<20‑30)	min	Prevent degradation; approx. 20 min allowable residence at 205 ℃ for POM‑K.
Shutdown procedure	Short‑term shutdown	Drop barrel temperature to 150	℃	Thoroughly purge barrel for long‑term shutdown.
	Barrel purging material	PE / PP	—	Do NOT use PVC or halogen‑containing materials for purging to prevent violent reaction. Turn off heating.
Post‑treatment	Annealing (if required)	120‑130 ℃, 2‑4 h or wall‑thickness dependent	—	Relieve internal stress and improve dimensional stability for high‑precision or non‑ambient‑service parts.

Note: All data above is for reference only！