Plasticisers vegetables

In the manufacture of baker s yeast, the stock strain is inoculated into a medium that containing molasses and com steep liquor. The pH of the medium is adjusted to be slightly acidic at pH 4-5. The acidic pH may retard the bacterial growth. The inoculated medium is aerated during the incubation period. At the end, the cells are harvested by centrifuging out the fermentation broth, and they are recovered by filter press. A small amount of vegetable oil is added to act as plasticiser, and then the cell mass is moulded into blocks. The process is shown in Figure 1.2. 

Acute oral toxicity studies for seven days on rats using the plasticiser emulsified in vegetable oil showed no clinical signs of toxicity with dose levels 0.2, 1.0 and 5.0 ml per kg body weight and no significant histopathological changes were observed. 

As well as the direct production of polymers, vegetable oil derivatives have other uses in the polymer industry, for example as additives. Materials made from vegetable oil have many uses and are used to produce anti-static, slip, and plasticising agents, stabilisers, processing aids and as flame retardants (see Section 2.4.). They can also be incorporated into the manufacture of polyamides, polyesters and polyurethanes. 

Namral vegetable fibre/plasticised natural vegetable fibre-a candidate for low cost and fully biodegradable composite. 

H.M. (1999) Natural vegetable fi-bre/plasticised natural vegetable fibre-a candidate for low cost and fully biodegradable composite. Adv. Compos. Lett., 8, 231-236. 

Polyvinylchloride (PVC) films have found wide applications in the packaging of a large variety of foodstuffs, such as fresh meat, fruits and vegetables, and cheeses [1]. These commercial films, in addition to the polymeric component, contain a number of additives. The one used in the highest proportion is the plasticiser. 

Barium/cadmium (Ba/Cd) and barium/cadmium/zinc (Ba/Cd/Zn) based stabilisers are general purpose stabilisers for plasticised PVC. Large quantities are consumed in leathercloth, calendered sheeting, extrusions, injection moulded footwear and flooring. They are not suitable for cable extrusion due to their inferior electrical properties. They exhibit synergism with phosphite chelators such as tris nonyl phenyl phosphite, and are often used with 3-5 phr of epoxidised vegetable oils as co-stabilisers. 

Phosphite chelators such as tris-nonyl phenyl phosphite are used as co-stabilisers with Ba/Cd and Ca/Zn to improve heat and light stability at an addition level of about 0.5 phr. Similar co-stabilising effects are shown by the epoxidised vegetable oils such as epoxidised soya bean oil, used at 3-5 phr. Epoxies may also be used at higher levels of 10-15 phr as secondary plasticisers to improve low temperature performance, when their presence also improves compound heat stability. Epoxidised soya bean oils are regarded as non-toxic and are therefore widely used as co-stabilisers in rigid and flexible food packaging applications. 

Small amounts of vegetable oil added to a natural rubber/ polybutadiene blend compound during mixing has a very significant effect on both vulcanisation and physical properties. Some of the effects may be from a lower crosslink density, or plasticisation. 14 refs. 

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