Material

Solid Silicone Sheet

Non-cellular silicone rubber with custom thicknesses and firmnesses for the hardest sealing requirements

Solid silicone sheet / silicone rubber sheet materials are inventoried by Stockwell Elastomerics from .010″ (0.25mm) to .500″ (12.7mm) thick and 10 to 70 durometer (hardness) Shore A. Stockwell Elastomerics inventories and fabricates the full line of NORSEAL® (formerly COHRlastic®) silicone rubber sheet materials and many silicones provided by the Rogers BISCO® and ARLON® product lines and several others to match the right product for our customers’ requirements.

Product availability ranges from general purpose and military specification grades, high flex / high tear strength grades, new liquid silicone rubber sheet (LSR) products that have exceptional elongation properties, silicones with UL 94 flame ratings, electrical conductivity and thermal conductivity among other properties.

Visit the Solid Silicone Data Sheets page for detailed technical information on each solid silicone product.

Stockwell Elastomerics regularly applies 3M and Adchem pressure sensitive adhesive backings to solid silicone. More detailed technical information about applying acrylic adhesive, silicone adhesive and combination adhesive to solid silicone is available.

What is Solid Silicone Rubber?

Solid silicone rubber is chemically identified as polymerized siloxanes or polysiloxanes; these are mixed organic-inorganic polymers. Compared to other silicone rubber materials such as silicone foam, silicone sponge, or silicone gel, solid silicone is different because it has no air pockets or interconnected open/closed cells. It can have many distinct formulations for custom properties: color, thickness, durometer, thermal performance, electrical performance, fire resistance, compression properties, and chemical resistance. It is compatible with many converting processes, and is generally specified by durometer, typically 10 shore A – 80 shore A.

The group of materials called solid silicone has these characteristics:

Wide temperature service range
Flexibility over that range of temperature, and notably good at low temperatures
Inert
Low toxicity
High biocompatibility
Good ultraviolet (UV) and ozone resistance

Silicone Sheet in Continuous Rolls

Stockwell Elastomerics maintains a full inventory of solid silicones that have been calendered and rotocured in 36″ wide continuous rolls, in thicknesses from .015″ to .125″ thick. Silicone sheet that has been calendered and cured in an autoclave or rotocured will usually have tighter thickness tolerances than molded sheets.

Most manufactured silicone rubber sheet is cured from gum based silicone – specifically methyl vinyl silicones, which meet a number of military, AMS and industrial specifications. These common silicones have a durometer range of 25 to 70 shore A, and the temperature range for these silicones is generally -100ºF to 500ºF.

The methyl-based gum silicones can be compounded to have high elongation, flex, tensile and tear properties for mechanically demanding properties. Stockwell Elastomerics inventories high strength silicone sheet in thicknesses and durometers ranging from .015″ to .125″ thick and in 30, 50 and 70 Shore A.

Relatively new liquid silicone rubber sheet (LSR) is cast and cured into thin gauge continuous rolls from .010″ to .032″ thick in 36″ widths. The most commonly available LSR sheet materials are provided in 10 to 40 durometer Shore A. LSR compounds have a platinum cure system, which decreases out-gassing and makes these silicone products more friendly to electronic, medical and optical applications.

Ultra-Thin Silicone Rubber with Pressure Sensitive Adhesive Backing

In response to requests for very thin display gaskets and pads needed for IP67 sealing and improved ruggedization of portable devices that may be exposed to weather extremes, Stockwell Elastomerics developed adhesive lamination capability for .010″ and .020″ thick BISCO HT-6000 series liquid silicone rubber sheet materials. Designers seeking a very thin, resilient gasket material with an adhesive backing benefit from this capability.

Specialty Silicones in 12″ x 12″ Molded Sheets

Stockwell Elastomerics has in-house compression molding capabilities, which allows us to provide 12″ x 12″ molded gum based silicone sheets in virtually any thickness from .020″ through .500″ thick. Fast-turn and short run molding of custom silicone sheets in many non-standard compounds, durometers and specifications are available for prototyping and initial production requirements. Examples of special compounds include phenyl based silicones for extreme low temperature (-130ºF), flame retardant, semi-conductive and electrically conductive silicones, thermally conductive silicones and others.

Stockwell Elastomerics has also developed a 12″ x 12″ injection molding process to support the needs of customers requiring liquid silicone rubber (LSR) in sheets, .032″, .062″, .125″ and .188″ thick. The present durometer range is 5 to 70 durometer shore A. Special colors and pressure sensitive adhesive backings are often provided on sheets molded with this unique capability – these are often water jet cut into made-to-order gaskets from customers’ electronic dxf files.

SG Series Spec Grade Solid Silicone

Stockwell Elastomerics offers a high consistency rubber (HCR) gum based specifications grade solid silicone that is idea for various gasketing, sealing and cushioning application in high temperatures or extreme environments. This robust, flexible material can conform to surfaces creating weather tight seals with moderate deflection forces. It is available in thicknesses from 0.020″ to 0.50″ and durometers as shown in this table and the SG Series Spec Grade Solid Silicone data sheet.

SG Series – Specification Grade General Purpose Solid Silicone

Property	Test Method	SG-30 GP	SG-40 GP	SG-50 GP	SG-60 GP	SG-70 GP
Durometer, Shore A	ASTM D2240	30	40	50	60	70
Tensile Strength, psi	ASTM D412	725	800	850	800	800
Elongation, %	ASTM D412	750	700	550	500	325
Tear, ppi die “B”	ASTM D624	75	110	125	150	130

SG Series solid silicone in all five durometers is stocked and immediately available in red; black or gray are also available upon request.

Its properties include:

Extreme low and high temperature resistance
Low compression set and stress relaxation compared to other solid elastomers
Dielectric barriers
UV / ozone resistant
Specifications: A-A-59588 2A/2B, (formerly ZZ-R-765 2A/2B), ASTM D2000, AMS 3301, AMS 3302, AMS 3303, and AM S3304

Silicone Sheet in 36″ x 36″ Molded Sheets – Specification Grade (SG) Molded Silicone Sheet

Stockwell Elastomerics inventories 36″ x 36″ gum based silicone sheet in .188″ (3.18mm) through .500″ (12.7mm). Also in inventory is 50 durometer silicone in every standard gauge (.188″, .250″, .375″ and .500″) and 30, 40 and 70 durometer silicone in many gauges from .188″ through .500″.

This Specification Grade (SG) Molded Silicone Sheet offered by Stockwell Elastomerics fills a need for thicker gauge 36″ x 36″ sheets in 2 thicknesses: 0.375″ and 0.500″. These are gum based, peroxide cured compounds made in 5 different durometers: 30, 40, 50, 60 and 70. SG-300 to SG-700 silicone sheets are compounded with iron-oxide pigment, molded flat and post cured for 4 hours at 450°F to improve service in high temperature applications such as heat sealing, annealing and other high temperature uses. Other suppliers previously made .375” and .500” thick sheets that were produced on a rotocure, and the resulting cured silicone had a noticeable curl. In contrast, SG-300 to SG-700 sheets are molded flat to best serve the intended use.

Solid silicone rubber sheet material is readily fabricated into gaskets and cushioning pads. Stockwell Elastomerics’ fabrication capabilities include die cutting, adhesive lamination, slitting to width and waterjet cutting of prototypes and production components. More technical details are available in the Specification Grade (SG) Molded Silicone Sheet Series technical data sheet.

Specifications Met by Silicone Rubber

The most frequent specifications requested are A-A-59588, also sometimes shown as AA-59588, AA 59588, or A A 59588. The previously used military specification was ZZ-R-765, ZZ-R-765b or ZZ-R-765e; ZZ-R-765 is now listed within A-A-59588. A-A-59588 Class 1 calls out extreme low temperature phenyl base silicone, A-A-59588 Class 2 calls out high temperature, low compression set methyl-vinyl silicone, and A-A-59588 Class 3 calls out high tear strength grades of silicone.

What is A-A-59588?

A-A-59588 is a General Services Administration specification for commercial use of silicone rubber in 6 different classifications. It defines the durometers (from 40A to 80A) as well as material properties and temperature resistance, varying on the class and configuration.