Polyurethane Dispersions for Coatings, Adhesives and Sealants
Over past decades, because of the increasing concerns on environmental issues and sustainability necessaries, industrial demanding with coating and adhesive solutions has begun a change from solvent-borne towards water-based systems.
Therefore, access to water-based systems has become critical. Witcobond® PUDs offer innovative and effective solutions for water-based polyurethane systems in many industries.
More than 40 years ago Lanxess, developed Witcobond® polyurethane dispersions (PUD). These dispersions enable a system to customers for complying with high demanding regulations about volatile organic content (VOC).
One another advantage with these PU dispersions is to help for providing high performance and high solids products; so, they can be used for bringing solutions to specific application needs. Lanxess’ portfolio is complemented by the special blocking technology which offering fully reacted polyurethane dispersions combined with the blocked systems for 1K and 2K stoving applications.
Benefits of Witcobond® PUD
• Balanced portfolio with strong performance in high solid grades,
• Water-based blocked crosslinkers for 1K and 2K stoving systems,
• More than 40 years of experience and ability of customize for applications,
• High quality and batch to batch consistency.
Providing a Range of Solutions to Satisfy Required Levels of Performance and Durability
Witcobond® polyurethane dispersions covers a broad range of products that formulators can choose according to their water-based coating systems for their special needs. Lanxess Witcobond® PU products are both ester and ether types with anionic, nonionic and cationic
grades. Formulators of water-based coating systems can choose from our broad range of.
For the properties such as hardness, flexibility, toughness and chemical resistance, these PU dispersions can help to formulators to get different variations.
Key Features:
• Solids contents varying from 30% to 60% w/w,
• Co-solvent and surfactant-free grades available for optimizing HS&E requirements,
• Compatibility with a wide range of aqueous co-binders, such as acrylic dispersions,
• Compoundable with pigments, matting agents, flame retardants and other auxiliaries.
WITCOBOND® Polyurethane Dispersions Can Be Used in Water-Based Coatings With or Without Crosslinkers
For improving the properties such as chemical resistance, coating adhesion, and robustness of a product, Witcobond ® polyurethane dispersions can be crosslinked with various agents.
Trixene® Aqua range belongs to Lanxess family, can be used for 1K or 2K stoving systems.
Trixene® Aqua contains water-dispersed latent crosslinkers and adhesion promoters. Under the effect of heat, these blocked isocyanates start crosslinking with complementary functional groups in the coating and substrate.
Fiber Sizing and Composites
Fiber sizing and composites industry is one of the most developing and critical ones on nowadays. Lanxess’ polyurethane dispersions are widely used in the fiber sizing industry.
Moreover, these products can be tailored for new requirements. Witcobond® polyurethane dispersions offer superior bonding of filaments in fiber and composite processing, and outstanding physical properties in end applications.
Witcobond® 374-13 is a polyester-based polyurethane dispersion that is commonly used as the film former in glass sizing recipes. It confers excellent integrity for chopped strand production and good adhesion with various thermoplastic and thermosetting matrices.
Adhesion between matrix and fiber can be further improved by using blocked isocyanate technology. And additives such as Trixene® Aqua BI 201 can be added to the normal
size formulation for getting alternative solutions.
Soft grades such as Witcobond® 374-13 can be incorporated into coating formulations that modify the haptics of normally harsh surfaces. Such coatings protect the base materials used in e.g. automotive interior facias and teletronic components, and provide improved aesthetics.
Coating of Hard Substrates Alternatively, hard products such as Witcobond® 781 and Witcobond® 457-66 can be used in durable, chemically-resistant 1K and 2K systems
applied to hard substrates such as wood, metals, glass, plastics, concrete and masonry. These application areas can be critical for today’s fast moving and changeable
environment.
Textile Processing
In textile processing, waterborne polyurethane dispersions such as Witcobond® 363-02 and Witcobond® 737 are being used on a broad range. Typical applications are full waterproof and weatherproof coatings, back coatings, laminating adhesives, pigment binders used in textile printing, and clothing with imperceptible finishes on yarns and fibers.
Other functional textile uses include protective coatings on belts, ropes, braids, optical
fibers and filament yarns. Lanxess’ applied research in water-based technologies present more greener technologies and chemistry for customers, formulators and end-users.
Besides the polyurethane dispersions, for coating, adhesive and sealant application areas and solutions, the portfolio covers the products like blocked isocyanate, blocked prepolymer
and innovative Low Free (LF) isocyanate systems. All of these products can offer key solutions for your systems and help to get expected properties on your products.
Özlem Erkan Asmaoğlu
PU & Coating Additives Technical Sales Engineer
Kimsel Kimya
