Innovative New Resins for Adhesion to Difficult Substrates
Generally, there are no substitutes for a clean, well-prepared surface to allow coatings and adhesives to adhere well to their substrates. However, choosing the proper resin can help to extend the working life of acrylic coatings and adhesives by providing better adhesion to various material types.
Mitsubishi Chemical Group's Elvacite® acrylic resins have long been the leader in quality adhesive and coating resins for substrate materials such as plastics, metals, concrete, wood, and paper. Recently, Mitsubishi Chemical Group released new adhesive and coating resin options specifically targeted at improving adhesion to difficult substrates like metals and plastics.
Metals, including aluminum, steel, copper, and zinc, are frequently used in environments that require a protective coating to prevent corrosion and rust. Adhesives that bond metals are also gaining popularity as stress on joints can be distributed across the bond line rather than concentrated at fastening sites. Bonding to metal can be tricky, and light sanding and a primer are usually necessary. Elvacite® 4347 is a methyl methacrylate acrylic resin that provides outstanding adhesion to untreated and unprimed metals. It also has the flexibility, outdoor durability, and abrasion resistance needed for the most challenging applications and environments.
|Appearance||White, spherical beads|
|Chemical Composition||Methyl Methacrylate Copolymer|
|Acid Value (mg KOH/g)||7.5|
Sometimes, the initial adhesion of a coating or adhesive may be good. However, adhesion issues arise once high stress is applied to the bond. This type of adhesive failure is usually due to a lack of flexibility and is a common issue for packaging applications where flexible films are utilized. Elvacite® 4345 is a low Tg butyl methacrylate resin ideal for adhesives and coatings applied to smooth plastic and metallized films. This resin can also be used to plasticize other resins to improve flexibility and adhesion to flexible substrates.
Click here for a starting point formulation for a flexible laminating adhesive based on Elvacite® 4345 resin.
|Appearance||White, free-flowing bead|
|Chemical Composition||N-butyl Methacrylate|
|Acid Value (mg KOH/g)||0|
Polypropylene, polyethylene, and thermoplastic olefins are popular materials in many applications because they are lightweight, durable, and inexpensive. These surfaces are difficult to adhere to and typically require surface preparation prior to painting or bonding. Elvacite® 4036 is a methacrylate copolymer resin that has shown improved adhesion to untreated polyolefins while providing the high degree of weatherability, gloss, and abrasion resistance expected of an acrylic resin.
Click here for a starting point coating formulation based on Elvacite® 4036 resin.
|Chemical Composition||Methacrylate Copolymer|
|Acid Value (mg KOH/g)||3.5|
Many substrates require extensive surface preparation and treatment for acceptable adhesion to occur. Elvacite® acrylic resins are ideal coating and adhesive resins that allow excellent adhesion to a variety of untreated materials that are typically hard to bond to. In addition, coatings and adhesives that use Elvacite® resins benefit from superior weathering resistance, abrasion resistance, gloss, and the ability to fine-tune the degree of flexibility required for each application. ChemPoint offers several resources below to assist you in developing coatings and adhesives with Elvacite® acrylic resins.
Need help choosing a grade? Click the link below to visit our Elvacite® acrylic resin selection guide and walk through resin selection step by step.
Looking for inspiration? Click the link below to visit our Elvacite® acrylic resin starting point formulation library.