Seatons Natural Oils for use in construction products
Croda offers a variety of natural vegetable oils that have applications in a diverse range of construction products. Oils can be processed to tailor their properties so they are suitable for use in the following:
Vegetable oils can be used to produce sand cores for use in metal castings. An oil is mixed with sand and then baked to form the core. The core needs to have sufficient strength to retain its form during the casting process but be able to be broken and removed afterwards. Oils that are suitable for this application are oxidised linseed and soyabean oils and polymerised soyabean oil. These oils all have reduced drying times and, in the case of the blown oils, increased reactivities.
Seatons emulsifiable rapeseed oil can be used to control dust when sprayed in an emulsified form. This product is a much better option in terms of safety, health and the environment than the mineral oil alternatives.
This traditional product is a flexible, hard wearing floor covering. It consists of a binder, an inorganic filler and an organic filler such as ground cork. Oxidised linseed oil can be used in the binder formulation where its drying properties and acid values are utilised when the other ingredients are added and the product cured.
Natural oils can be used as plasticisers in a wide range of construction products to give flexibility, workability and resilience. They also have health and safety advantages over phthalates, which have been traditionally used. Oils that are suitable include oxidised castor, linseed, soyabean and rapeseed oils.
Castor oil and oxidised rapeseed oil can be formulated into rigid polyurethane foams. Castor oil can be supplied as a polyurethane grade, which has a very low moisture content. Once reacted with isocyanates, it gives tough, durable, chemically resistant urethane polymers – both rigid and expanded types.
Putty is a traditional product used to hold glass window panes into their frames. It is produced by blending calcium carbonate with raw linseed oil. Croda can supply raw linseed oil with an enhanced acid value to aid the wetting abilities of the oil when mixed with calcium carbonate.
Sealants and mastics
Oxidised soyabean and castor oils can both be used to produce mastics and sealing compounds. Mastics have replaced putty to some extent as, when applied, they give a solid surface that can be painted; yet below the surface the formulation retains plasticity and gives movability. Oxidised castor oil (often 30 poise @ 25°C) is often added as a plasticiser.
Boiled linseed oil can be used to seal and waterproof concrete, brickwork and terracotta tiles. It is absorbed by the substrate and dries quickly to seal and protect. The oil should be diluted with white spirit (50%) and then applied to the cleaned surfaces with a brush or roller. A second coat can be applied after 24 hours if necessary.