Cellulose, additives Plasticisers

Digestible substrate (cellulose fiber, plasticisers, and other consumable additives, as well as low molecular weight fragments of plastic, with molecular weight lower than 500. They can form as a result of thermal- and photooxidation of plastics (see Chapter 15))... 

Nitration of cellulose followed by plasticisation of the product with camphor has the effect of reducing the orderly close packing of the cellulose molecules. Hence whereas cellulose is insoluble in solvents, except in certain cases where there is chemical reaction, celluloid is soluble in solvents such as acetone and amyl acetate. In addition the camphor present may be dissolved out by chloroform and similar solvents which do not dissolve the cellulose nitrate. 

Although the prime function of plasticisers in cellulose acetate is to bring the processing temperature of the compound below the polymer decomposition temperature, it has additional values. An increase in the plasticiser content will reduce the melt viscosity at a given temperature and simplify processing. The physical properties of the finished product will be modified, increasing toughness... 

As a result of development work between the Battelle Institute in Frankfurt and a German candle-making company, Aetema, biodegradable cellulose acetate compounds have been available since 1991 from the Rhone-Poulenc subsidiary Tubize Plastics. They are marketed under the trade names Bioceta and Biocellat. The system is centred round the use of an additive which acts both as a plasticiser and a biodegrading agent, causing the cellulose ester to decompose within 6-24 months. 

In 1991 Rhone-Poulenc offered biodegradable cellulose acetate compounds in which an additive acts both as plasticiser and biodegrading agent (see Section 22.2.2.1). 

APCI-MS/MS is not only useful in the analysis of polymers, such as cellulose acetate, but is also of great value in the identification of copolymer substrates, and the various polymer additives such as antioxidants, stabilisers, and plasticisers. 

More than 600 products are used in the manufacture of different paper grades from the cellulose fibres of trees. These products include fillers, preservatives, plasticisers, whitening agents, chelators, adhesives, dispersing agents, corrosion inhibitors and many other additives (Fregert 1976). 

Wood furniture coatings usually contain urethane/isocyanates in addition to UF, volatile plasticisers, residual solvents and free monomers from incomplete polymerisation of the coating. Nitrocellulose lacquer, acrylic, cellulose acetate butyrate and polynrethane (with plasticisers like epoxy, di-bntyl phthalate, butyl benzyl phthalate and isopropyl myristate) are the coatings commonly nsed on clear finished wood furniture. In these, the amonnts and... 

Quantitative analytical schemes (using calibration curves, internal standardisation) have been devised for selected (copolymeric) systems [540]. An example is the determination of the composition of styrene-methacrylate by PyGC [603]. Qther applications include the quantification of rubber components [604,605], cellulose esters [606], isocyanate components of polyurethanes [607], nylon [608], plasticisers [609], aliphatic sulfur-containing additives [4]. Standardisation for quantitative analysis based on PyGC data requires careful choice of reference polymers. Use of an internal standard may improve the precision when the concentration of a single polymeric component of a blend or copolymer is calculated on the basis of PyGC data [610]. 

PE/cellulose or scrap paper cellulose fibres, LDPE/plasticised starch, and 40% wood-filled HDPE are found to increase breaking strengths, impact properties, and heat deflection temperatnre, in addition to reducing water absorption. 

In order to confer such necessary properties as heat sealability and moistureproofness, the base cellulose film is topcoated with a lacquer of either modified nitrocellulose or vinylidene chloride copolymer. The former system was developed in the late 1920 s and is based on nitrocellulose plasticised with organic esters. In addition, paraffin wax and resins are added to confer moistureproofness. This type of coating can be modified to give only partial moistureproofness or, if necessary, can be made non-heat sealing. 

Small ECDs with good electrochromic properties have been realised with such SPE, ° the natural polysaccharides such as cellulose and starch derivatives can be modified by a plasticisation process with glycerol, and after addition of lithium salts, transparent films with high ionic conductivity can be obtained. " ... 

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