HTML\RTV Silicone Rubber

RTV Silicone Rubber

1. Properties:

Telechelic polymer, composed of polydimethyl siloxane with two active terminal and fillers and additives.

Stored in soft metal tube, convenience operation.

Excellent insulating properties and chemical inertness, wide working temperature range(-60^oC~200^oC).

Resist water, ozone and weather aging.

Good adhesion to lots of metal and nonmetal.

GD -401 and GD-402 have a little erosion to metal and the characteristics of fast surface cure, send out small amount of acetic acid in the process of curing.

GD-406,GD-407 and GD-414 have no erosion to metal and other materials.GD-406 is designed specially for surface protection of silicon components and possess the properties of low passivaton coefficient,
good adhesion, can obviously decrease electrical leakage of core of electron tube and increase the capacity of H-voltage resistance and the silicon components have good surface self-cleaning property.

GD-414 possesses the properties of fast-cure, good adhesion, high mechanical strength, subsidence and flow resistance.

2. Main Applications:

Mainly used as insulating, moisture-proof, shock-proof coating and capsulation materials for electrical components and equipment.

Also as sealant(such as forming-on-the-spot sealant for cylinder sleeve of automobile engine, temporary leakage block-up of industrial pipe and equipment),packing material and adhesive, etc.

3. Specification: back to top

**Note:" <= " means no more than , "=>" means no less than**
Brand	GD-401	GD-402	GD-404	GD-406		GD-407	GD-414
Appearance	Fluid	Paste	Fluid	White fluid	Paste	White fluid	White, red black paste
Surface solidifying time (min.)	30~180	30~180	15~60	15~60	<= 200	<= 240	10~70
Hardness (Shore A)	=> 25	=> 30	=> 25	=> 30	-----	-----	-----
Tensile strength at break MPa	=> 0.59	=> 0.98	=> 0.69	=> 1.86	-----	=> 1.96	=>3.92
Elongation at break %	=> 200	=> 200	=> 200	=> 250	-----	=> 200	=> 300
Dielectric coefficient 106Hz F/m	<= 3.2	<= 3.5	<= 3.2	<= 3.5	3.0~ 3.5	<= 3.5	-----
Brand	GD-401	GD-402	GD-404	GD-406		GD-407	GD-414
Dielectric loss tangent 106Hz	<= 5X10^-3	<= 5X10^-2	<= 5X10^-3	<= 5X10^-2	<= 5X10^-3	<= 5X10^-3	-----
Volume resistance Ohm-cm	=>1X10¹³	=>1X10¹³	=>1X10¹³	=>1X10¹³	=>1X10¹⁴	=>1X10¹⁴	-----
Puncture strength MV/m	=> 12	=> 10	=> 15	=> 15	=> 15	=> 15	=> 15
Shearing strength MPa	-----	-----	-----	-----	=> 0.78	=> 1.47	=> 1.47
Tearing strength N/m	-----	-----	-----	-----	-----	-----	=> 1.18X10⁴

Directly extrude the paste or fluids out of the soft tube. Curing take place as soon as the paste touch the moisture in the air, but they become elastomer by degree from outside to inside and solidifying time is directly proportionate to thickness of the rubber.

( ***Temperature 20***^oC~30^oC, Relative humidity 60~80%.)
Solidifying Time (hr)
Thickness	GD-401	GD-402	GD-404	GD-405	GD-406
0.5~1 mm	1~2	1~3	0.5~1	0.5~1	2.5~4
1~2 mm	2~4	2~4	1~2	1~2	-----
2~3 mm	4~10	5~10	3~6	3~6	-----
3~4 mm	10~20	15~20	6~14	6~14	3~6
7~9 mm	~48	~48	40~48	40~48	-----
10~11 mm	~72	~72	48~60	48~60	-----

Curing will fail if the work-piece is sealed up as soon as it is applied paste, so the silicone rubber must be exposed to air for a relative long time to cure thick rubber sheet.

Curing by stage can be employed if fast deep cure is needed(spread the paste small in quality one time, repeat the process after previous spreading rubber solidified thoroughly until reaching required thickness).

Adding 5~20 parts MgO into 100 parts GD-404,GD-405 can make deep cure and eliminate erosion of the by products(extrude the paste into beaker, put into MgO, stir till well distributed).

If working temperature higher than 150^oC and the rubber layer relatively thick or the work-piece is air-tight, the giving off low molecular weight by products are not admitted, three stage curing process can be employed: Dry at temperature, treat at 40¡æ~50¡æ in a oven of relative humidity 90%,then,dry at 180¡æ~200¡æ to fulfill cure, remove low molecular weight by products and improve the propertied of the rubber.

As packing and adhesive materials, the work-piece should be clean and dry. As packing material, lay the work-piece aside for certain time before use. As adhesion, first apply the paste to work-piece, lay aside for a little while to let the rubber layer absorb some moisture, finally, put the two waiting-for-adhering surfaces together and lay aside for 24 hours.

Notes: back to top

These silicone rubbers are cured by moisture in air and emit low molecular weight materials, raising temperature and increasing relative humidity would accelerate the curing process.

As the volume coefficient of expansion(6~8X10^-4/ ^oC) is much larger than that of metal, it must be took into consideration when using at high temperature.

5. Packing, Storage and Transportation:

Packing: 50g net in soft metal tube.

Storage: Keep dry. Keep away from sunlight and rain during storage and transportation.

Shelf time: 1 year. Beyond the time, it still can be used after being tested and qualified

Transportation: As non-hazardous chemicals.

RTV Silicone Rubber

1. Properties:

2. Main Applications:

3. Specification: back to top

4. How to use: back to top

5. Packing, Storage and Transportation: