The document provides information on the thermoplastic polymer polyoxymethylene (POM) including its delivery program, properties, applications, and chemical resistance. POM has a continuous service temperature up to 100°C, high surface strength surpassed by few materials, and good sliding and wear resistance due to its strength and smooth surface. It has applications in bearings, fittings, gears, pumps, and textiles. POM demonstrates resistance to many chemicals at room temperature and 60°C but is not resistant to strong acids or oxidizing agents.

1. Thermoplastische Kunststoffe
Thermoplastics
Thermoplastiques
Lieferprogramm Halbzeuge
Delivery Program Stock Shapes
Programme de livraison semi-produits

2. POM
GEHR POM-C® GEHR POM-C® (Acetal) GEHR POM-C®
Polyoxymethylen besitzt eine Dauerge- Polyoxymethylene can be used in Le polyoxyméthylène possède une
brauchstemperatur bis 100 °C. Die hohe temperatures up to +100 °C. The high tempé-rature d’utilisation en continu
Oberflächenhärte wird nur von wenigen surface strength is only surpassed by a jusqu’à 100 °C. La dureté de surface
Kunststoffen übertroffen. Aufgrund der few materials. élevée n’est dépassée que par de rares
hohen Härte und der glatten Oberfläche POM shows good sliding properties and plastiques. Grâce à sa dureté élevée et
besitzt POM ein gutes Gleit- und high resistance to wear and tear because à sa surface lisse, le POM présente une
Verschleißverhalten. Die Neigung zu of the high strength and smooth surface. bonne tenue au glissement et à l’usure.
Spannungsrissen besteht grundsätzlich There is a very low risk of stress cracks. Il ne présente, par définition, aucune
nicht. Das Copolymer besitzt eine hohe POM-C (Copolymere) exhibits a high propension aux fissures sous contrainte.
Thermostabilität und Chemikalienbe- thermal stability and a high resistance Le copolymère possède une thermosta-
ständigkeit (hier ist besonders die ge- to chemicals (high resistance to hydro- bilité et une stabilité chimique élevées
steigerte Hydrolysebeständigkeit zu be- lysis). (il convient de noter particulièrement, en
achten). Properties: l’occurrence, la résistance accrue à
POM
Eigenschaften: • no microporosity l’hydrolyse).
• druckbeständige Qualität • high strength Propriétés :
• hohe Härte und Steifigkeit • high rigidity (to -40 °C) • Qualité de résistance à la pression
• hohe Zähigkeit (bis -40 °C) • high thermal stability • Dureté et rigidité élevées
• hohe Wärmeformbeständigkeit • low water absorption • Grande ténacité (jusqu’à -40 °C)
• geringe Wasseraufnahme • high dimension stability • Grande résistance à la déformation
• hohe Dimensionsstabilität • good electrical insulating properties thermique
• gutes elektrisches Isolierverhalten • very good sliding properties • Faible absorption d’eau
• sehr günstiges Gleitreib- und • high resistance to solvents • Grande stabilité dimensionnelle
Gleitverschleißverhalten • very high resistance to stress cracks • Bon comportement à l’isolation
• hohe Beständigkeit gegen Lösungs- • not resistant to high-concentrated électrique
mittel acids • Comportement très favorable au
• hohe Beständigkeit gegen Span- • difficult to glue and paint frottement dynamique et à l’usure par
nungsrissbildung Applications: glissement
• nicht beständig gegen starke Säuren Bearings, fittings, gear wheels, parts for • Grande résistance aux solvants
und Oxidationsmittel pumps, screws, bobbins, parts for the • Résistance élevée à la formation de
• schlechte Verkleb- und Lackierbarkeit textile industry, medium for coating lines. fissures sous contrainte
Anwendungsbeispiele: • Ne résiste pas aux acides et agents
Lagerrollen und -käfige, Beschläge, d’oxydation forts
Zahnräder, Pumpenkörper, Schrauben, • Mauvaise tenue à la colle et à la
Bauteile in der Feinwerk- und in der peinture
Textiltechnik, Träger für Lackierstraßen. Exemples d’application :
Rouleaux-supports et cages de paliers,
ferrures, roues dentées, corps de
pompes, vis, armatures de bobines,
composants pour la mécanique de
précision et la technique des textiles,
supports pour cabines de peinture.
42
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3. POM
W
GEHR POM-C® GEHR GEHR GEHR WEARGEHR NE
Vollstäbe Toleranzen POM- POM- POM- POM-
ø Tolerances ELS ® ESD ® ESD-FG® 10PE ®
Round Rods mm
Tolérances
mm
min. max. kg/m kg/m kg/m kg/m kg/m
Joncs pleins
3 0,012 0,012
L: 1000 / 2000 / 3000 mm 4 0,025 0,025 NE
W
+ 0,4
5 0,032 0,032 0,031 0,032
+ 0,1
Farben, Colours, Couleurs: 6 0,045 0,045 0,043 0,046
natur, natural, naturel 8 0,079 0,078 0,076 0,080
+ 0,5
schwarz, black, noir 10 0,121 0,120 0,116 0,123 0,123
blau (~RAL 5002), blue, bleu 12 0,176 0,175 0,168 0,179 0,170
hellblau, light blue, bleu clair 15 0,271 0,269 0,259 0,275 0,261
elfenbein, ivory, ivoire 16 + 0,7 0,307 0,305 0,294 0,311 0,327
18 0,386 0,383 0,369 0,392 0,372
20 0,474 0,471 0,454 0,481 0,460
22 0,575 0,571 0,550 0,583 0,554
+ 0,2
25 0,740 0,735 0,708 0,751 0,726
+ 0,9
28 0,930 0,923 0,890 0,943 0,896
30 1,060 1,053 1,014 1,075 1,043
32 1,210 1,202 1,158 1,227 1,166
36 + 1,1 1,520 1,509 1,455 1,542 1,463
40 1,870 1,857 1,790 1,897 1,831
45 2,370 2,353 2,268 2,404 2,332
50 + 1,3 2,920 2,900 2,794 2,962 2,864
56 3,650 3,624 3,493 3,703 3,518
+ 0,3
60 4,200 4,171 4,019 4,260 4,123
65 + 1,6 4,920 4,886 4,708 4,991 4,829
70 5,690 5,650 5,445 5,772 5,586
75 6,570 6,524 6,287 6,665 6,333
POM
+ 0,4 + 2,0
80 7,460 7,408 7,139 7,567 7,314
85 8,430 8,371 8,068 8,551 8,127
+ 0,5 + 2,2
90 9,430 9,364 9,025 9,566 9,258
100 + 0,6 + 2,5 11,650 11,568 11,149 11,818 11,458
110 + 0,7 + 3,0 14,150 13,640
120 16,900 16,470
+ 0,8 + 3,5
125 18,300 17,641
130 19,800 19,437
135 + 0,9 + 3,8 21,350
140 22,900
150 + 1,0 + 4,2 26,350
160 + 1,1 + 4,5 30,000
165 31,200
+ 1,2 + 5,0
180 37,900
200 + 1,3 + 5,5 46,800
210 51,970
230 + 1,5 + 6,2 61,900
250 72,900
300 108,700
+ 7,0
350 145,600
0
400 189,700
+ 10,0
500 287,400
44
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4. Technical Data Sheet
Polyoxymethylene POM-C
I. Physical Properties
Test method Unit Value
1. Specific gravity (ρ) ISO 1183 g/cm³ 1,39
2. Water absorption DIN 53495 % 0,2
3. Maximum permissible service temp - - -
(no stronger mechanical stress involved)
Upper temperature limit - °C 110
Lower temperature limit - °C -50
II. Mechanical Properties
Test method Unit Value
1. Tensile strength at yield ISO 527 MPa 63
2. Elongation at yield. (εS) ISO 527 % 10
3. Tensile strength at break (σR) ISO 527 MPa -
4. Elongation at break (εR) ISO 527 % 31
5. Impact strength (an) ISO 179 kJ/m2 no break
6. Notch impact strength (ak) ISO 179 kJ/m2 6
7. Ball indentation / Rockwell hardness ISO 2039-1 MPa 135
8. Shore-D DIN 53505 85
9. Flexural strength (σB 3,5 %) ISO 178 MPa -
10. Modulus of elasticity (Et) ISO 527 MPa 2600
III. Thermal Properties
Test method Unit Value
1. Vicat-softening point VST/B/50 ISO 306 °C 150
VST/A/50 ISO 306 °C -
2. Heat deflection temperature HDT/B ISO 75 °C 155
HDT/A ISO 75 °C 95
3. Coefficient of linear thermal expansion α DIN 53752 K-1∗10-4 1,1
4. Thermal conductivity at 20 °C (λ) DIN 52612 W/(m∗K) 0,31
IV. Electrical Properties
Test method Unit Value
1. Volume resistivity VDE 0303 Ω∗cm ≥1013
2. Surface resistivity (Ro) VDE 0303 Ω ≥1013
3. Dielectric constant at 1MHz (εr) DIN 53483 - 3,8
4. Dielectric loss factor at 1 MHz (tanδ) DIN 53483 - 0,005
5. Dielectric strength VDE 0303 kV/mm 40
6. Tracking resistance DIN 53480 - CTI 600
V. Additional Data
Test method Unit Value
1. Bond ability - - fair
2. Friction coefficient DIN 53375 - 0,35
3. Flammability UL 94 - HB
4. UV stabilisation - - fair
All values are attributes of the used raw materials.
The physical data contained in this table are typical values. They are obtained on test specimens under specific conditions and
represent average values of a large number of tests. The results obtained on this tests specimens cannot be applied to finished
parts without reservations, as behaviour is influenced by processing and shaping. Reproduction only with our definite permis-
sion.
Subject to change without notice. Page 1 of 1 Date: 11/04

5. Chemical Resistance
GEHR POM-C
conc. (%) room temperature 60 °C
1,4 Dioxane 100 o o
2-Hydroxypropionic acid 90 + -
Acetic acid 100 o -
Acetone 100 + o
Ammonia conc. + +
Ammonium chloride +/o o
Amyl alcohol +
Apple juice +
Benzene o o
Bleaching solution 12,5 Cl - -
Boric acid 100 o/- -
Brake fluid +
Butyl acetate + o
Calcium chloride + +
Carbon disulphide 100 + +
Carbon tetrachloride + o
Chlorine, gas 100
Chlorobenzene 100 o o
Chloroform - -
Citric acid 10 o -
Cresol
Cyclohexanone 100 +
Cyclohexene 100 +
Diesel fuel + +
Diethylene oxide, THF + +
Ethyl acetate 100 o o
Ethyl alcohol 96 + o
Ethylene chloride 100
Food oil + +
Formaldehyde, aqu 40 + +
Formic acid 10 + -
Frost protection agent +
Fuel , aromatic free + +
Glycerin 100 + o
Glycol 100 + +
Heating oil + +
Heptane 100 + +
Hydrochloric acid 10 - -
Hydrochloric acid conc. - -
Hydrofluoric acid 40 -
Hydrogen peroxide 10 + -
Hydrogen sulphide +
Isopropyl alcohol 100 + +
Linseed oil + +
Mercurochrome -
Methyl alcohol 100 + +
Methyl ethyl ketone 100 o o
Dok.-Nr. Name Erstelldatum/Geändert am Erstellt von Seite
POM_engl Chem-Best 11.12.2007 QM 1 von 2

6. Chemical Resistance
GEHR POM-C
conc. (%) room temperature 60 °C
Methylene chloride 100 - -
Milk + +
Mineral oils, aromatic free + +
Nitric acid 10 - -
Nitric acid 50 - -
Nitrobenzene o
Oxalic acid -
Ozone, gas ca. 0,5 ppm - -
Paraffine oil 100 + +
Perchloroethylene + o
Petroleum ether 100 +
Petroleum, aromatic free 100 + +
Phenol, aqu ca. 9 - -
Phosphoric acid 50 - -
Potassium hydroxide liquor 50 o
Premium Fuel + +
Propyl alcohol
Pyridine
Silicone oil + +
Sodium carbonate, aqu + +
Sodium chloride, aqu + +
Sodium hydroxide liquor 15 + o
Sodium hydroxide liquor 60 o
Sodium hyrogen sulphite - -
Sodium nitrate, aqu + +
Sodium thiosulfate
Sulphuric acid 96 - -
Tetrahydrofurane 100 o o
Toluene 100 + +
Transformer oil + +
Trichloroethylene 100 o o/-
Vinegar, standard 5-10 + +
Water + +
Xylene + +
Symbolism for the description of the chemical resistance
+ = resistant (only small changes of the weight, dimensions and properties.
According our experiences there is no permanent damage expect).
o = partly resistant (medium changes of the properties. At longer contact time there are
permanent damages recommended e.g. degradation of the macro
molecular structure).
- = non resistant (strong and permanent degradation in short contact time e.g. stress
cracking).
= not tested (no tests were done, no recommendations are possible).
The figures indicated here are approximate values. They may be affected by the temperature, operating time, concentration and
stress level of the component involved, by mechanical loads, etc., and the user is not released therefore from the obligation of
performing checks and trials of his own. The values indicated here have been compiled on the bases of current experiences and
findings. Any legally binding guarantee of certain properties, or any suitability for a specific application cannot be inferred from
the present data.
Dok.-Nr. Name Erstelldatum/Geändert am Erstellt von Seite
POM_engl Chem-Best 11.12.2007 QM 2 von 2

7. GEHR GmbH GEHR Plastics, Inc. GEHR Plastics Hong Kong Limited
Casterfeldstr. 172 Naamans Creek Center Unit 2, 11/F,
68219 Mannheim 24 Creek Circle Fonda Industrial Building,
Boothwyn, PA 19061 37-39 Au Pui Wan Street
Fotan, Shatin
Germany USA Hong Kong
T: +49 - 621-87 89 - 0 T: +1 - 610 - 497 - 8941 T: +852 - 6977 - 33 18
F: +49 - 621-87 89 - 200 F: +1 - 610 - 497 - 8901 F: +852 - 3013 - 9544
info@gehr.de info@gehrplastics.com info@gehr.hk
www.gehr.de www.gehrplastics.com www.gehr.hk
GEHR Plastics China Office GEHR Plastics Bureau France GEHR Plastics Ufficio Italia
Room 1003, No. 7 6 Rue de la Chapelle DIPRO
New Phoenix Town Ginza 39700 Serre les Moulières Via Alessandria 55
51 Feng cheng road 10152 Torino
200093 Shanghai
China France Italy
T: +86 - 21 - 51 69 28 72 T: +33 - 7 - 86 48 38 04 T: +39 - 011-24 89 507
F: +86 - 21 - 60 91 93 03 F: +49 - 621 - 87 89 - 200 F: +39 - 011-24 85 733
info@gehr.cn info@gehr.fr info@gehr.it
www.gehr.cn www.gehr.fr www.gehr.it
3.11.11. STO
Änderungen vorbehalten. Subject to change. Sous réserve de modifications.