POLYACETAL (POM)

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