Instant Bonding Water-Based Contact Adhesives for Foam Lamination and Bonding

Quickbond™ AB2550-PFB and AB2750-EFB Water-Based Adhesive by Coral Industries of AIT Chemical, Inc.

Coral Industries of AIT Chemical, Inc. is proud to introduce a novel water-based adhesive designed and tested to have the combination of fast tac setting (rapid initial bond strength buildup), forming an ultimate bond strength exceeding that of the intrinsic foam strength.

Quickbond™ AB2550-PFB water-based adhesive is a contact adhesive that achieves instant handling strength in less than 60 seconds or less. It has been molecularly engineered to achieve one of the highest bond strengths that exceeds the strength of the typical open-cell foams of most chemistry types, and non-ethylene type closed cell foams. This heat-resistant adhesive is flexible with the capability of a one-surface contact adhesive application for increasing productivity.

Quickbond™ AB2750-EFB is the only known water-based contact adhesive for expanded polyethylene (EPE, both crosslinked and non-crosslinked, soft and hard) foam-to-foam and foam to substrates bonding adhesive without the use of primer, pressure or heat. It can be used with one-side surface adhesive application method and provide immediate handling green strength and achieve strong bonding within 30-60 minutes in ambient. 
Both AB2550-PFB and AB2750-EFB are proven for used with porous and non-porous substrates exceeding the speed of setting and bond strength the best in the water-based contact cements.

Mastering Water-Based Adhesives for Foam Bonding

Water-based contact adhesives (contact cements) are characteristically different from the more traditional solvent-based contact adhesives for foam bonding. The first obvious difference is the fact that water as carrier or “solvent” in water emulsion or dispersion has much lower vapor pressure or rate of evaporation that most of the solvents used in solvent-borne contact cement.

The second being the compatibility between the contact adhesives to the substrates being bonded together. That is, whether the contact adhesive can form good bonding or will be de-bonded or separated easily with any pull or shear forces. Traditional solvent-borne contact cement is referred to as rubber cement reflecting the fact that they dried or set to a rubbery like adhesive. These rubber cements have been engineered to have high compatibility to most substrates and particularly foams as substrate. Water-borne contact cements are typically acrylic, polyurethane, and neoprene chemistry that have different polarity or compatibility to the different foam substrates.

The third is the mechanical rigidity and other physical and chemical properties. Foams are classified as open-cell and closed-cell foams with closed-cell foam typically used in more rigid format while open-cell foams are typically engineered to be more flexible and compressible or compliance. The water-based cements selected for bonding should not materially changed the over-all mechanical rigidity characteristics. This is more critical when selecting water-based adhesive or contact cement for the multi-layering or bonding of flexible foam to flexible foam. While rigid foam commonly used for packaging can use with flexible or rigid adhesive.

There are three major factors and considerations in selecting the right water-based foam adhesive:

• Compatibility matching between foam adhesive with foam material chemistry for long-lasting strong bonding:  
  
  • Open-cell foams are predominantly based on polyurethane, EVA, and polyurethane, required specialty foam contact cement or adhesive for fast to instant bonding
  • Closed cell foams depend on material chemistry can be polar such as expanded polystyrene (Styrofoam) or non-polar such as expanded polyethylene (EPE)
• Matching speed of tack-bonding time with the usage requirement:
  
  • Specialty foam adhesive can achieve almost instant bonding for most of the open-cell foams, while close cell foam to foam bonding can take quite a bit longer-time to form good handling bond 
    
• Matching flexibility of the foam adhesive to the compressibility of the foam for low and temperature requirement:
  
  • Flexible foam-to-foam applications will require the adhesive to be similar flexibility to ensure compressibility. Even for bonding onto rigid substrates such as wood or metals, flexible adhesive also ensures long-term reliability when low temperature excursion is expended.