Polymers, Resins, Dispersions, Emulsions
Carst & Walker (South Africa) has established itself as a significant agent and distributor of materials as well as offering technical support for these growing sectors, providing:
Acrylic & Modified Acrylics
Ethylene Vinyl Acetate (EVA) copolymers are thermoplastic compounds produced by co-polymerisation of ethylene and vinyl acetate monomer to produce a random branched structure. A major constituent in the production of hot melt adhesives for packaging and bookbinding, EVA’s are essential to the modern adhesive manufacturer. Carst & Walker offers a wide range of RESPSOL ALCUDIA EVA copolymers, and with vinyl acetate proportion (VA%) varying from 3% to 33% and viscosity ranges between MFI (Melt Flow Index) 0.8 and 800, almost all applications are catered for.
Hydrocarbon resins have broad compatibility with a large range of oils, resins and polymers including EVA, natural rubber, SIS, SBS, SEBS thermoplastic elastomers and paraffinic waxes. They are soluble in the common solvents used in industrial adhesives and paint manufacture.
Used as tackifiers or for end-block reinforcement, Carst & Walker offers a wide range of Hydrocarbon Resins for production of hot melt adhesives, solvent based adhesives & coatings and the manufacture of thermoplastic traffic paints.
From liquid resins to 150 °C softening point resins; from water white to dark yellow almost any application is provided for. Light coloured C5 aliphatic, C9 aromatic and C5/C9 hybrid resins and water white AMS resins are regular stock items.
Natural / SIS / SBR / SBS / NBR Rubbers
Carst & Walker offers a wide range of natural and synthetic rubbers for the production of hot melt adhesives, solvent based adhesives and bitumen/asphalt modification.
Our range of Styrene-Isoprene-styrene (SIS) rubbers vary from 15% styrene content to 30% styrene, with di-block content ranging from <1% to 52%. They are widely used in the production of pressure sensitive hot melt adhesives and solvent based adhesives for production of labels and tapes.
Our specialist range of hot polymerised Styrene Butadiene rubbers (SBR) are characterised by very low gel content and recommended for a variety of adhesive and sealant applications. When incorporated in a solvent along with appropriate tackifier, un-crosslinked polymers produce tacky cements for bonding, coating and sealing applications, including tapes and labels where a good balance of adhesion, cohesion and tack is required. Partially Crosslinked SBR Polymers produce adhesives and sealants with a non-stringy, buttery consistency and are particularly useful for caulking compounds, mastics and sprayable adhesives.
Carst & Walker offer an extensive range of Styrene–Butadiene-Styrene (SBS) rubbers. Products ranging in styrene content from 25% to 40% are stock items but a wide range of dry and oil extended grades are available on request.
A range of SEBS rubbers are also available on request.
Several of our extensive range of Nitrile rubbers (NBR) are used in the production of solvent based adhesive cements. Useful for applications where chemical resistance is required, our range of 33% – 41% acrylonitrile grades are widely utilised in adhesive applications.
Our natural rubber (NR) is available as 60% FA latex or pre-vulcanised latex as well as solid/sheet form.
Carst & Walker offer a range of hot melt polyamide adhesives. Featuring excellent high / low temperature cycling, moderate to long open times and good chemical and grease resistance, they are widely used in multipurpose assembly, packaging and woodworking industries. Specialist grades exhibit excellent adhesion to plastics including plasticised PVC.
Non-yellowing, and heat resistant, polyamide adhesive resins are extremely versatile and many grades carry FDA approval under code 175.105.
Polychloroprene rubber (neoprene) is a synthetic rubber made by polymerizing 2-chlorobuta-1,2-diene. Polychloroprene is often used in place of natural rubber in applications requiring resistance to chemical attack.
Carst & Walker are proud of their association with Denka Japan and offer a range of medium and rapid crystallising polychloroprene rubber grades, suitable for the production of solvent based contact adhesives. Low solution viscosity and high solution viscosity grades are offered as regular stock items.
Metal Oxides (MgO, ZnO), Phenolic Resin, Antioxidants and other ingredients used in the production of contact adhesives are available from Carst & Walker.
Polyvinyl alcohol (PVA, PVOH, Poval) is a water-soluble synthetic resin manufactured by hydrolyzing polyvinyl acetate, which is obtained through polymerization of vinyl acetate monomer. By diversifying the specific degrees of polymerization and hydrolysis, polyvinyl alcohol is produced in various types and grades. The unique qualities of polyvinyl alcohol are utilized as an ingredient in a wide variety of applications such as ingredient in film and acetal resin, fibre processing agents, adhesives, vinyl chloride polymer stabilizers, and inorganic binders.
Carst & Walker offers a limited range of Poval grades ex stock, ranging from partially hydrolysed (88%) to fully hydrolysed (99%), and low viscosity (4-6) to high viscosity (40-50). A full range of grades is available on request.
Aliphatic and Aromatics Poly Urethane Dispersions wide range a of hardnesses and properties from textile (tenting) coatings to floor wall wood plastic and meny other with exceptional resistance to abrasion, oils, fats, solvents and chemicals.
Rosin & Rosin Esters, Phenolics
Gum rosin, or colophony, is a hard translucent resin, obtained as a solid residue from crude turpentine. Usually pale yellow or amber, its colour may vary from brownish-black to transparent depending on the grade. It is soluble in alcohol, ether, turpentine, and several other organic solvents, and in solutions of various metal hydroxides.
Rosin is not a pure substance but a mixture of several compounds, chiefly abietic acid. It is used in making varnishes, paints, sealing wax, adhesives; as a sizing material for paper; in the preparation of certain metals for soldering. Athletes commonly rub it (in the form of dust) on their hands or the soles of their shoes to prevent slipping. Both WW and WG grades of rosin, from Chinese and Brazilian sources, are available on request.
A wide range of Rosin esters manufactured by ARIZONA CHEMICALS are available from Carst & Walker. The tackifier of choice in many hot melt and solvent based systems, the premium SYLVALITE range of resins are used in the production of pressure sensitive and packaging adhesives. Ranging from liquid tri-ethylene glycol (TEG) esters, to glycerol and pentaerythritol (PE) esters with softening points up to 115 °C, the extensive range of ester resins available are sure to satisfy the most demanding of applications.
Carst & Walker offers a range of alkyl phenolic resins particularly suited to the adhesive formulator producing solvent based contact adhesive cements based on polychloroprene rubber. Phenolic resins influence the adhesion, open time and peel strength of these systems.
Carst & Walker offers a range Vinyl acetate-ethylene copolymers (VAE) from our Japanese partner Denka. Characterised by having superior adhesion, excellent elongation, water resistance, flexibility and rapid setting speeds, the EVATEX emulsions are particularly suited to the adhesive formulator producing packaging adhesives for high-speed packaging machine applications and PVC lamination.
Vinyl Chloride Resins
Carst & Walker’s line of VA/VC co-polymer resins consists of a range of molecular weight and bound acetate levels to provide for wide latitude of formulating variability. Co-polymers are used in place of PVC homopolymers, because the internal plasticizing affect of the vinyl acetate makes them easier to process on conventional equipment. The vinyl acetate also gives exceptional pigment wetting characteristics when high levels of filler are to be used.