Abstract |
CapatueTM MCA-633 (Zinc acrylate (ZDA) with CAS number 14643-87-9) is a difunctional solid acrylate salt for use in peroxide cured elastomers(NBR, EPDM, CPE, BR, SRB, Silicone) where enhanced adhesion and dynamic properties are needed. It is an economical way to enhance the performance of peroxide-cured elastomers. CapatueTM MCA-633 (Zinc acrylate (ZDA) with CAS number 14643-87-9) is available at a fraction of the cost of other commonly used agents and yield comparable, even superior, mechanical properties.
Its function is similar to Dymalink® 633 from Cray Valley of Total Company.
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Identification |
Chemical Name |
: |
Zinc acrylate |
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Molecular Structure: |
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|
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Molecular Formula: |
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2(C3H3O2).Zn |
Molecular Weight: |
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207.50 |
CAS Registry Number: |
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14643-87-9 |
EINECS: |
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238-692-3 |
Equivalents |
Dymalink® 633 from Cray Valley of Total Company
Saret® SR633 from Sartomer Company
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Specifications |
Appearance: |
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Off-white powder |
Specific Gravity: |
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1.59 |
Mesh: |
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≥100 |
Crosslinking with peroxide results in the formation of a covalent bond as shown in (A). This carbon-carbon bond is quite rigid and stable and accounts for the lower tensile and tear strength of peroxide cured stocks compared with sulfur vulcanizates. The good heat stability of this covalent bond also explains the superior heat aged characteristics of peroxide cured systems.
In contrast, polysulfide crosslinks formed in sulfur cure are thermally weak but are mobile under stress and can slip along the hydrocarbon chain. This mobility has been used to explain the superior tensile and tear strength in sulfur cured stocks.
The Capatue™ metallic coagent-peroxide crosslink bond is "ionic" as shown in (B) below. The technology and characteristics of this ionic bond have been detailed in the literature for the commercial ionomers. This ionic bond exhibits both good heat aged stability and the ability to slip along the hydrocarbon chain and reform.
Thus, this unique system embodies the best characteristics of both the peroxide and sulfur crosslink systems, giving high tensile and tear strength and excellent heat aged properties.
1. Performance Advantages
Peroxide curing with Capatue™ metallic coagents significantly enhances the performance of a variety of elastomers. These easy-to-handle, 100% reactive solids yield strong rubber-to-metal bonds and other highly desirable performance advantages, including:
Greatly improved heat aging
High tensile strength
High tear strength
Higher modulus
Higher hardness
Increased abrasion resistance
Improved resilience
Very high rubber-to-metal adhesion
2. Processing Advantages
Capatue™ Metallic coagents contain a patented none-nitroso scorch retarder for safe, easy processing.
High scorch safety
100% reactive solids
Non-volatile
Easily dispersed free flowing powders
Low odor
Available in pre-weighted, low melt polybutadiene bags
3. Cost Advantages
Capatue™ Metallic coagents are an economical way to enhance the performance of peroxide-cured elastomers. They are available at a fraction of the cost of other commonly used agents, such as HVA-2, and yield comparable, even superior, mechanical properties.
Capatue™ metallic coagents in peroxide cured stocks and can be used with elastomers such as hydrogenated nitrile rubber (HNBR), polybutadiene (BR), ethylene propylene diene rubber (EPDM), silicone, styrene butadiene rubber (SBR), natural rubber (NR), chlorinated polyethylene (CPE) and others. The retarder increases the scorch time, thus providing processing safety. It has no deleterious effect on aged or unaged physical properties. The typical applications includes:
Rubber
Adhesive
Plastic
Cable & Wire
Capatue™ metallic coagents are compatible and mix well with most rubbers. To insure maximum dispersion of all formulation ingredients and to minimize sticking, it is recommended that a certain "order of addition" be followed. This procedure applies for the two roll mill as well as the Banbury internal mixer.
1. Introduce the rubber stock and process for approximately 30 seconds. There is no need to "break down" the rubber before adding the formulation ingredients. The initial high rubber viscosity will aid in dispersing the additives.
2. Add the Capatue™ coagent and process just long enough to encapsulate the powder. This procedure minimizes sticking and interaction between the coagent and certain processing aids.
3. Add fillers and processing aids.
4. Add the peroxide curative.
5. Mix and blend as appropriate. Use standard processing temperatures and cycle times.
Depends on different formula and application, the regular dosage of this product is roughly 3~15 PHR, the user should determine the best dosage by lab test before their production line application.
The regular packing of this product is paper bag or fiber drum, 20kg/bag or 20kg/drum.
Store in a cool and preferably air-conditioned area where the ambient temperature does not exceed about 32ºC. Keep containers tightly closed until ready to use so as to avoid loss of activity. The Capatue™ coagents are anhydrous salts that will readily absorb moisture upon exposure to a humid atmosphere. For optimum results, use within 6 months of receipt.
The shelf-life of CapatueTM MCA-633 (Zinc acrylate (ZDA)) is six months from date of purchase when stored in its original packaging, temperatures between 10ºC and 32ºC and out of direct sunlight.