Plastic water-soluble

Occasionally, water-soluble plastics are required. Poly(vinyl alcohol) is commonly the first to be considered but some cellulose ethers, polyethylene oxides, poly(vinyl pyrrolidone) and A-substituted polyamides are among many possible alternatives. 

PVPO is highly polar and water-soluble plastic. It finds applications in adhesives and as a water thickener. Water solutions can be used as blood plasma substitute or artificial blood. 

To be effective, a plasticizer must partition from the solvent phase into the polymer phase and subsequently diffuse throughout the polymer to disrupt the inter-molecular interactions.The rate and extent of this partitioning for an aqueous dispersion have been found to be dependent on the solubility of the plasticizer in water and its affinity for the polymer phase. The partitioning of water-soluble plasticizers in an aqueous dispersion occurs rapidly, whereas significantly longer equilibration times are required for water-insoluble plasticizing agents. For aqueous-based dispersed systems, water-insoluble plasticizers should be emulsified first and then added to the polymer. Sufficient time must be allowed for plasticizer uptake into the... 

Polyoxyethylene is another water-soluble plastic that has been known for a number of years but has seen little use. There are conflicting reports about its biodegradability. Mitsubishi is the major supplier. 

Water-soluble plasticizers are used in most cases unless improved water protection is... 

Water sensitivity and solubihty can be conveniently regulated by the use of a combination of plasticizers. In hotmelts that are water sensitive, two groups of plasticizers are used in different proportions depending on required properties. Larger amounts of water soluble plasticizers such as polyethylene glycol mono- and di-laureates increase water sensitivity. Addition of larger amounts of water insoluble plasticizers, such as 2-ethyl-hexyl diphetyl phosphate or butyl benzyl phthalate, increases the hydrophobic properties of hotmelt. ... 

One of the first manufacturers of polyvinyl alcohol (PVOH) was Air Products Chemicals, which manufactured it under the Airvol trade name. It appears that the product may no longer be available, however. Another early manufacturer was ChrisCraft Industrial products, Inc., which still makes PVOH through its Monosol division. Another major supplier is Kuraray, which makes a variety of water soluble plastics, including PVOH under the name Poval. DuPont sells PVOH under the Elvanol tradename and Polyval under the name Enpol. There are other supphers as well. 

Diacetin n. (glyceryl diacetate. (1,3-diacetin), and 1,2-diacetin, a mixture of isomers. A water-soluble plasticizer, and a solvent for cellulose nitrate and cellulose acetate See image). 

Fifty percent of TEA plasticized NaCAS films with various ratios of crosslinker were immersed into distilled water. The exudation ratio of TEA (percentage of initial dry weight of TEA initially present in films) versus immersion time is shown in Fig. 5. As suspected, the water-soluble plasticizer exudes out of the film and after 10 min immersion in distilled water 80% of the TEA migrated out of the film, whatever the crosslinking. For all the NaCAS films, the whole TEA exuded out of the film after 24 h in water. Nevertheless, for short time of contact with water (2 min), the plasticizer... 

Vezin and Florence (1980) used monodisperse powdered polymer particles for studying the in vitro degradation of poly(7j-alkyl a-cyanoacrylates), with a range of alkyl side chains and MW. These authors showed that degradation in aqueous buffer depends not only upon the pH and the length of the polymer alkyl side chain, but also critically on the polymer particle surface, particle size, polyoner MW and MW distribution. They concluded that at low MW (below the characteristics of effective tissue adhesiveness), increased water solubility, plasticity and diffusivity may result in a bulk rather than surface polymier degradation. 

Schaffer, E. (1978). Water soluble plastics in the preservation of artifacts made of cellulosic materials. In 5th triennial meeting Zagreb, 1-8 October 1978 Preprints, International Council of Museums Committee for Conservation. 

Polyvinyl alcohol is one of the few water-soluble plastics, and its main use is derived from its ability to be formed into a film for sachet production. This is useful for adding metered amounts of chemicals (dangerous or otherwise) to water in order to make up standard solutions. 

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