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Chemicals |
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Antistatic Agents |
Trade Name |
Chemical Nature |
Apparance at 25°C |
Available form of packing |
Addition level |
Used in Polymer |
Main Function |
Armostat 300 |
ethoxylated amine |
paste |
drums,
180 kg net |
0.1-0.15 |
PE-PP |
int. antistat |
Armostat 400 |
ethoxylated amine |
liquid |
drums,
180 kg net |
0.1-4.0 |
PE-PP-PS-ABS-SAN |
int. antistat |
Armostat 600 |
ethoxylated amine |
solid |
drums,
180 kg. net |
0.1-0.15 |
PE-PP |
|
Armostat 1000 |
alfa-g.m.s. |
pellets |
PE-bags,
25 Kg net |
0.1-1.0 |
PE-PP-PS-PVC |
int. antistat |
Armostat 2000 extrudates |
fatty alkanol amide |
off-white extrudates |
PE-bags,
20 Kg net |
0.1-0.8 |
PE-PP |
int. antistat |
Armostat 2004 |
fatty alkanol amide |
powder |
cardboard box, 20 Kg net |
0.1-0.8 |
PE-PP |
int. antistat |
Armostat 3002 |
Na sec. alkyl sulphonate |
off-white flakes |
PE-bags,
20 Kg net |
1.0-2.5 |
PET-PC-PA-PVC-PS |
int. antistat |
Electroconductive Carbon Black
Trade Name |
Chemical Nature |
Apparance at 25°C |
Available form of packing |
Addition level |
Used in Polymer |
Main Function |
KetjenBlack
EC-300J |
special Carbon Black |
pelletized Black |
PE-bags
(10 Kg net) |
10-15 |
All polymers |
Carbon black imparting electrical conductivity |
KetjenBlack
EC-600JD |
special Carbon Black |
pelletized Black |
PE-bags
(8 Kg net) |
6-15 |
All polymers |
Carbon black imparting electrical conductivity |
Methods for Determination of Electrical Properties
of Polymeric Materials
The most reliable way to assess the performance of polymers containing anti-static agents is by determination of charge decay behaviour. Although there is no linear relation between charge decay times and surface resistivity levels, there is a certain correlation between these properties.
In table 1, an indication for the rating of antistatic performance using surface resistivity and charge decay methods is shown. |
Performance rating at 45% R.H. / 22°C
| Table 1 |
ASTM D-257 Surface Resistivity |
ASTM F-365 Decay Half Time |
| Rating |
S.R. (Ohms) |
t 1/2 (s) |
| Excellent |
<1011 |
<1 |
| Good |
1011-1012 |
1-10 |
| Moderate |
1012-1013 |
10-100 |
| Poor |
1013-1014 |
>100 |
Choice Of Antistatic Agents / Addition Levels
The best way to choose an anti-static agent, and its addition level, depends on the nature of the polymer, on the type of machinery, on the process conditions, on the presence of other additives and on the moisture level.
The general guide lines for Armostat addition levels are shown in Table n°2. |
| Table 2 Polymer
| Ethoxylated amines %
| Glicerol mono-stearate %
| Fatty alkanol amides %
| Na alkyl Sulphon. %
|
| PE
| 0.1-0.15
| 0.1-1.0
| 0.1-1.5
| *
|
| PP
| 0.1-0.15
| 0.3-1.0
| 0.4-0.8
| *
|
| PVC
| *
| 0.5-2.0
| *
| 0.5-2.0
|
| PS, HIPS
| 1.0-4.0
| *
| *
| 1.0-4.0
|
| ABC, SAN
| 1.0-4.0
| *
| *
| 1.0-4.0
|
| PET, PBT, PA
| *
| *
| *
| 1.0-3.0
|
*= Not recomended
N.B.: The time needed to obtain a good antistatic performance level, normally varies from 0 to 72 hours of machinery, depending on Armostat type and addition level. An excessive use of antistatic can, however, have a greasy effect to the surface of the finished products and get the moulding difficult.
If the finished products had to be used in Food Contact Applications, the max. approved addition level depends on local regulations. |
FERRO-PLAST Srl distributes in Italy the Akzo Nobel Chemical's Antistatic Additives (Armostat) and Electroconductive Carbon Blacks (Ketjenblack).
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