Water based acrylic polymer emulsions are environmentally friendly adhesives that provide a balance between shear (the ability of the adhesive to stick to itself), tack (the degree to which the adhesive bonds immediately to the adherend), and peel (the bond strength between the adhesive and the adherend, which typically increases over time during the curing process). Many acrylic polymers are cross-linkable, giving the final adhesive or binding product weather and aging resistance as well as resistance to water, laundry detergents, and solvents. Examples of acrylic adhesives include PSAs (pressure-sensitive adhesives) and emulsion systems used to bond paper to paper for lamination. U.S. Adhesives manufactures acrylic adhesives for a wide variety of applications. With numerous products in our formulary and custom formulation available, we have the ability to exceed the expectations of our customers and potential new clients. A few of our most popular acrylic adhesives are listed below.
Natural rubber latex, obtained by tapping the Havea Brasiliensis tree, is commonly put to use in water based adhesives, where rubber particles are protected or stabilized by proteins and fatty acid soaps, with the latex component typically containing approximately 35% solids. Total solids in natural latex based adhesive formulations will vary, however, depending on the final application of the adhesive. In packaging as well as in converting, graphic arts, and certain textiles, natural rubber adhesive products have been in use for decades. The addition of wetting agents, stabilizers, and other additives dictates the application of each formulation. Natural rubber latex adhesives are most often applied to substrate by brush, spray, doctor knife, or reverse roll coater. U.S. Adhesives currently manufactures natural rubber latex adhesives for numerous applications and continues to develop new formulations as required by our customer base. A few of our most popular formulas are listed below.
SBR Latex is a carboxylated styrene butadiene copolymer. This synthetic rubber was developed during the Second World War as a means to increase rubber production. The rubber adhesive is durable and resistant to abrasion, heat, and cold, making it suitable for use in adhesives. SBR is produced from two monomers—butadiene and styrene. Butadiene is obtained from petroleum, butane, or ethyl alcohol. Styrene is obtained from petroleum or benzene. These monomers are converted to SBR in an emulsion polymerization process. SBR is used extensively for bonding fibrous materials, as a pressure-sensitive adhesive, and where the cost of natural rubber is prohibitive. U.S. Adhesives currently manufactures numerous SBR latex formulations and is actively developing new adhesive and binding products for market introduction. A few of our most popular SBR formulas are listed below.
Homopolymer emulsion based adhesive is the most commonly used adhesive glue due to its excellent adhesion to a wide variety of "polar" substrates, particularly cellulosic-based substrates such as paper and wood. Homopolymers are hard and brittle. Their high molecular weight, high tensile strength, rapid setting speed, and low cost make them the "workhorses" of the industry. Other characteristics such as its affinity for adhesion to ceramics, concrete, and glass make it an indispensable base for adhesive formulations. Commonly referred to as wood glue, white glue, and school glue, it is used in many industries, such as bookbinding, paper bag manufacturing, paper converting, carton sealing, labeling, etc. U.S. Adhesives offers a wide variety of PVA based products. A few of our most popular finished PVA emulsions are listed below.
Vinyl Acetate Ethylene (VAE) copolymers are water based emulsions, which offer considerable performance advantages over PVA homopolymers due to the ability to alter their glass transition temperature (Tg°C) through the incorporation of ethylene monomer. As ethylene content increases, glass transition temperature decreases.
VAEs offer comparable machining properties to PVAs with the added benefit of significantly improved adhesion to non-porous surfaces such as vinyl, aluminum, etc. VAEs also exhibit better flexibility, water resistance, and cost-performance while offering superior adhesive properties along with more user-friendly compounding characteristics. Flexible packaging adhesives constitute the largest area of application for VAEs. Included in this market segment are case and carton sealing, bonding of coated board, the manufacture of paper bags, etc. Laminating applications represent another large use for VAEs. Because of their flexibility, moisture resistance, and superior substrate adhesion, VAEs also find wide use in adhesives for furniture manufacture, bookbinding, textiles, and do-it-yourself projects. VAEs are also popular in the fabrication of non-woven products, such as toweling and diapers, and in the backing of fabrics and carpeting. U.S. Adhesives manufactures numerous VAE emulsion adhesives—a few of our most popular are listed below.
In industrial use, hot melt adhesives provide several advantages over solvent-based adhesives, such as excellent adhesion, reduction or elimination of VOCs, (volatile organic compounds). Typically, hot melt glue may be disposed of without special precautions and are relatively easy to use. Methods of applying hot melts vary from glue gun to closed system extrusion and spraying. These thermoplastic adhesives are used in packaging, converting, and bookbinding, as well as assembly and in the production of nonwovens and footwear. A lack of water and solvents allows this type of industrial glue to attain peak-bonding strength very quickly. These polymers wet-out and penetrate the bonding surface prior to solidifying as they cool down again. Hot melt adhesives are manufactured in pellets, chips, pillows, chubs, and glue stick form. The proper form depends on the application, size of operation, and the function of the hot melt adhesive in product production.
Hot Melt Glue Advantages
- Aggressive bond
- Reduced char
- Low/no odor
- No stringing/tailing
- Increased mileage
- Reduced viscosity gain
- Clean machining
- Speed of bond formation allows high line speeds
- Wide variety of application methods
- Bonds impervious surfaces
- Bonds non-porous surfaces
- Applicable for high humidity environments
- Long shelf life
- Zero volatile organic chemicals (VOCs)
U.S Adhesives offers the following types of hot melt adhesives:
Ethylene Vinyl Acetate (EVA): EVA, the most widely used and versatile hot melt base, is the cornerstone of the original hot melt composition. Adhesive grade EVA usually contains 14–35% vinyl acetate. Lower molecular weight chains provide lower melt viscosity, better wetting, and better adhesion to porous surfaces. Higher molecular weights provide better cohesion at elevated temperatures and better low-temperature behavior. EVA can be cross-linked, compounded with either aromatic hydrocarbon resins or natural terpene tackifying resins. This industrial glue is widely used in the following applications:
- Bookbinding
- Case and Carton Sealing
- General Packaging
- Appliance
- Doors and Millwork
- Furniture
- Multi-wall and Specialty Bag
- Pressure-Sensitive: These hot melts (chubs and pillows) provide aggressive bond strength, low temperature flexibility, and high heat resistance; they do not solidify, but remain tacky and wet-out substrates on contact.
- Metallocene: Formulations of this type of hot melt glue are the absolute highest performing adhesive technology available for packaging. They reduce production downtime because they do not char, so clogging of nozzles and filters is eliminated. Their low density and strong bond characteristics improve overall mileage. And lastly, metallocene adhesive glue produces bonds with high heat resistance and low temperature performance for freezer applications.
- Polyethylene: These low-density hot melts feature aggressive bonding properties and excellent thermal stability. U.S. Adhesives’ polyethylene hot melts are designed for case and carton sealing applications as well as multi-wall bag manufacturing.
- Polyurethane: Polyurethane Reactive (PUR) hot melt has a combination of different positive attributes found in various, unique adhesives. PUR hot melt is not found in the normal form of a glue stick or bulk pellet; instead, it is melted from a solid prior to application. PUR hot melt solidifies through moisture in the air to form a super strong bond that will not re-melt.
U.S. Adhesives is a leading hot melt adhesive manufacturer and distributor of EVA, PSA, metallocene, polyethylene, and polyurethane hot melt products. A few of our most popular hot melts are listed below.
Dextrin, a low molecular weight carbohydrate produced by hydrolysis of starch, is the main ingredient in certain water based adhesive and binding products. Dextrin adhesives are liquid glues manufactured by cooking to 200°F in water, which forms a solution that can be modified for tack, open time, and various other properties. Dextrin adhesives provide clean machining and excellent bonding properties to cellulosic materials, such as paper and paperboard. They exhibit high wet tack, are light straw to amber in appearance, and are typically cost effective. Dextrin applications include laminating, converting, printing, core winding, carton and case sealing, paper bag and envelope manufacturing. Their re-moistenability makes them useful in the manufacture of stamps and envelopes, and they are water soluble, which allows them to be cleaned easily. U.S. Adhesives currently manufactures numerous dextrin glues and is continually engaged in the development of new formulas for various applications and industries. A few of our most popular dextrin products are listed below.
Animal glue is derived from gelatin, which is extracted from collagen, a protein component of bovine and porcine hides, and then graded for use in the adhesive industry. It is an all-natural, non-toxic, and biodegradable product. Also known as protein colloid glue, this adhesive glue is formed through hydrolysis of collagen from skins, bones, tendons, and other animal tissues.
The first known procedures for making animal glue were written about 2000 BC. Between 1500–1000 BC, animal glue was used for wood furnishings and mural paintings and was found even on the caskets of Egyptian pharaohs.
The first commercial glue factory, manufacturing glue from hides, opened in Holland circa 1700. The United States' first glue factory, established by the Milwaukee Tanning Industry, opened in 1899. However, the eventual advent of synthetic adhesives heralded the collapse of the animal glue industry.
Today, animal glues are sparsely industrialized, but still used for making and restoring paintings, illuminated parchment manuscripts, and other artifacts. Synthetic glues such as polyvinyl acetate (PVA) and other resin glues have all but done away with the use of animal glue. It is, however, still used in specialty applications such as pipe organ building, piano repairs, antique restoration, and bookbinding. U.S. Adhesives manufacturers several grades of animal glue. A few of our most popular products are listed below.
U.S. Adhesives specializes in creating custom formulations that meet or exceed customer expectations. Our chemists have years of experience in formulating adhesives. Whether you require specific industrial glue, hot melt, dextrin, or water based technology, our state-of-the-art laboratory and development team will more than satisfy your needs. It is our mission to partner with our customers to create lasting solutions. Let us take the stress out of your product development initiatives by eliminating guesswork and costly testing of formulations that may not meet your application requirements. With over 500 existing adhesives in our formulary, we can modify or create new products per your specifications. Our commitment to current and prospective clients is to create new and innovative products the first time and every time. For more information, please contact us to discuss our services in detail.
