Crestamould® B21 Sealer

Identification & Functionality

Chemical Family

Polyesters

Polymer Name

Polyester (unspecified)

Reinforcement Form

Chopped Strand Mat,

Roving

Composite Materials Functions

Resins, Binders & Matrix Materials

Technologies

Composite Materials

Product Families

Composite Materials — Polymers & Resins

Thermoset Resins

Features & Benefits

Materials Features

Excellent Seal Properties,

Good Adhesion,

Good Sealant Properties,

Low Styrene Content

Applications & Uses

Markets

Industrial

Applications

Industrial — Chemical & Industrial Manufacturing

Tooling & Moldmaking

Plastics & Elastomers End Uses

Foams

Application

• Crestamould B21 sealer is suitable for use on a vast range of polystyrene grades but we recommend testing on your chosen grade before use, to ensure that it is suitable for your application.
• If separation has occurred, redisperse by thoroughly mixing the material until homogeneous. Ensure the polystyrene surface is clean before application.
• Apply by brush. A resin to glass ratio of 3:1 should be used and no more than 2 layers of 450g CSM at a time to reduce the exotherm and risk of degrading the polystyrene plug. It is important to avoid excess accumulation (>3mm thickness) of material on the substrate surface. Allow 1.5 - 2 hours between the application of the sealer resin and subsequent lamination. These general properties are based on an ambient temperature of 24°C.

Properties

Physical Form

Fiber,

Mat

Typical Properties in Liquid State

	Value	Units	Test Method / Conditions
Density	1.28 - 1.35	g/cm³	—
Viscosity (6.0)¹	1900 - 2400	mPas	—
Viscosity (0.6)²	7500 - 9500	mPas	—
Gel Time³	15 - 20	min	—

Note

¹ - RV1 Cone and Plate at 6.0 s⁻¹ (25°C)
² - RV1 Cone and Plate at 0.6 s⁻¹ (25°C)

³ - Gel time measured with 100g mass with 2% medium reactivity MEKP catalyst.
⁴ - Shelf life is defined from date of manufacture when stored as recommended.

Packaging & Availability

Packaging Information

Crestamould® B21 Sealer is supplied in 25kg pails and 5kg tins.

Storage & Handling

Shelf Life

6 months⁴

Storage Conditions

• Crestamold® B21 Sealer should be stored between 5°C - 25°C in the original, unopened container in a dry, well ventilated place. Protect from freezing and direct sunlight. Avoid contact with oxidizing agents. If stored outside of the recommended storage conditions shelf life will be significantly reduced.
• Mixing : Before using thoroughly mix contents. Do not remove any Crestamold® B21 from container before mixing.