RTV664

RTV600 Series Addition Cure Moldmaking Compounds

Product Description

MasterMolder’s RTV600 series is comprised of RTV662, RTV664, and RTV668. Each is a two part, addition (platinum) curing mold making product offering high durometer for applications requiring greater dimensional stability.

RTV662 offers the highest durometer (68 Shore A) in the series, as well as the longest worklife. It is ideally suited for embossing, release rolls, and large molds.

RTV664 is a high durometer (62 Shore A), long work life product. It offers excellent chemical and abrasion resistance and was designed for high production on manufacturing lines.

RTV668 is a high durometer (62 Shore A) product formulated for sulfur resistance. It is ideal for casting with masters made of pine, oak, and elm.

Key Performance Properties

Excellent dimensional stability
High tear strength
High durometers 62,68 Shore A
Virtually no shrinkage (room temperature cure)

Typical Product Data

Product Base	RTV662A	RTV664A	RTV668A
Color	beige	beige	beige
Viscosity, cps	150,500	153,000	151,000
Specific Gravity	1.28	1.28	1.28
Catalyst	RTV662B	RTV664B	RTV668B
Color	blue	blue	green
Viscosity, cps	5,000	6,000	3,800
Specific Gravity	1.05	1.05	1.05
Mix Ratio, wt:wt	10:1	10:1	10:1
Catalyzed Properties
Viscosity, cps	120,000	120,000	120,000
Worklife, hrs.	4	2	2
Potlife, hrs.	5	3	2.5
Demold time, hrs.	24	18	24
Shore A, 36 hrs.	68	62	62
Tensile, psi	1015	933	1041
Elongation, %	235	245	240
Tear, ppi	136	122	100
Service Temperature,C(F)	-60/200 (-75/392)	-60/200 (-75/392)	-60/200 (-75/392)
Linear Shrinkage, %	< 0.2	< 0.2	< 0.2
Shelf Life, months	12	12	12

Specifications

Typical product data values should not be used as specifications. Assistance and specifications are available by contacting GE Silicones at 800/255-8886.

Instructions for Use

Mixing

Select a mixing container 4-5 times larger than the volume of RTV silicone rubber compound to be used. Weigh out the RTV silicone rubber base compound and add the appropriate amount of curing agent. With clean tools, thoroughly mix the RTV base compound and the curing agent, scraping the sides and bottom of the container carefully to produce a homogenous mixture. When using power mixers, avoid excessive speeds which could entrap large amounts of air or cause overheating of the mixture, resulting in shorter pot life.

Deaeration

Air entrapped during mixing should be removed to eliminate voids in the cured product. Expose the mixed material to a vacuum of about 29 in. of mercury. The material will expand, crest, and recede to about the original level as the bubbles break. Degassing is usually complete about two minutes after frothing ceases.

Automatic equipment designed to meter, mix, deaerate, and dispense two-component RTV silicone rubber compounds will add convenience to continuous or large volume operations. For additional information, refer to GE Silicones publication (1758).

Curing

RTV662, RTV664, and RTV668 silicone rubber compounds will cure sufficiently in 24 hours at 25C (77F). To achieve faster cure speeds, elevated temperatures may be used.

Handling and Safety

Material Safety Data Sheets are available upon request from GE Silicones. Similar information for solvents and other chemicals used with GE products should be obtained from your suppliers. When solvents are used, proper safety precautions must be observed.

Storage and Warranty Period

The warranty period is 12 months from date of shipment from GE Silicones if stored in the original unopened container at 25C or below.

Availability

Products may be ordered from GE Silicones, Waterford, NY, 12188, the GE Silicones sales office nearest you or where appropriate, an authorized GE silicone product distributor

Government Requirement

Prior to considering use of a GE Silicones’ product in fulfilling any government requirement, please contact the Government and Trade Compliance office at 413-448-4624.