POLYACETAL (POM)

Polyacetals are polymers in which main chains contain acetal groups (-O-C-O-). They are obtained mainly in the process of aldehydes polymerisation. They are applied in various branches of electrical engineering, mechanical and automotive industries as well as in paint production, food and bottling industry, and also in manufacturing objects of everyday use.

PROPERTIES:

low friction coefficient
wysoka wytrzymałość mechaniczna, sztywność i twardość
high mechanical endurance, hardness and rigidity
abrasion and wear resistance
physiologically harmless, admitted to direct food contact
dimensional stability (low thermal expansion)
good creep resistance
great machinability
good sliding properties
high impact strength even in low temperatures
superb resilience
low water absorption

APPLICATION:

Low module sprockets, loaded sliding bearings, elements of electrotechnical and household devices, guides, scrolls, high precision elements of machines, construction elements with high dimensional stability, screws, cams, hooks, water supply systems and automotive subassemblies.

AVAILABLE COLOURS: white, black and dark brown.

MACHINING: Polyacetals can be processed on turning lathes and milling machines.

BASIC TYPES OF POLYACETALS:

POM C natural (white/black)
POM H natural (white)
POM C is a material which is highly resistant to hydrolysis. It is used in places where strong alkalia and thermal oxidative degradation occur. POM H, in turn, has a higher mechanical endurance, hardness, rigidity and creep resistance as well as higher abrasion resistance.

SPECIAL TYPES OF POLYACETALS:

POM H-TF (dark brown)
POM H-TF is a combination of TEFLON fibres, evenly diffused in acetal technical plastic. As a result of modification mechanical endurance similar to POM-H has been preserved. Thanks to addition of TEFLON fibres some of its properties have been changed, which means that POM H-TF is softer, less rigid and has higher sliding property than pure acetal plastic. In comparison with POM C and H, POM H-TF offers superb sliding properties; bearings made of this material display low friction coefficient, long lasting abrasion and they are free from abrasive vibration.

TECHNICAL INFORMATION

Properties	UNIT	POM
General properties
Density	g/cm3	1,42
Water absorption, saturation	%	1,8
Hygroscopic rate, saturation 230C	%	0,24
Mechanical properties
Hardness	H 961/30 N/mm2	150
Elongation at break	%	40
Tensile modulus	N/mm2	3000
Impact strength	kJ/m2	no break
Notched impact (Charpy)	kJ/m2	9
Time unit tensile (1% 1000h)	N/mm2	14
Tensile strength at yield	N/mm2	70
Thermal properties
Thermal dimensional stability A (ISO-R 75)	0C	105
Thermal dimensional stability B (ISO-R 75)	0C	155
Upper temporary service temperature limit	0C	140
Upper permanent service temperature limit	0C	105
Linear thermal expansion coefficient 23-1000C	10ExpE5x1/K	11
Thermal conductivity (230C)	W/Km	0,31
Fire class according to UL-Standard 94 HB	–	–
Melting point	0C	160
Electrical properties
Volume resistivity	0Hm cm	10Exp15
Dielectric constant	10E x p6 Hz	3,8
Dielectric dissipation factor	10E x p6 Hz	0,003
Dielectric strength	kV/mm	50
Surface resistivity	Ohm	10Exp13

RODS	POM
Density (g/cm3)	1,41
diameter mm	Weight kg/m
5	0,031
6	0,043
8	0,076
9	0,096
10	0,117
11	0,15
12	0,17
13	0,2
15	0,26
18	0,38
20	0,46
25	0,72
30	1,03
36	1,49
40	1,83
45	2,32
50	2,86
60	4,11
70	5,57
80	7,3
90	9,24
100	11,42
110	13,85
120	16,52
130	18,72
140	22,44
150	25,79
165	31,11
180	37,13
200	45,82
210	50,53
230	60,43
250	71,36

SHEETS	POM
Density(g/cm3)	1,41
diameter mm	Weight kg/m
1X1000	1,43
2X1000	2,86
3X1000	4,29
4X1000	5,72
5X500	3,88
6X500	4,7
8X500	6,17
10X1000	15,1
12X1000	18,46
16X1000	24,19
18X1000	27,05
20X1000	29,91
25X1000	37,07
30X1000	45,08
40X1000	59,39
50X1000	73,7
60X1000	88,73
70X500	52,28
80X1000	118,43
90X500	67,35
100X1000	147,05