Plasticizers cellulose acetate phthalate compatible

Several polymers were found to fit all or most of the above criteria and were used to prepare the carrier films. Many polymers have been used for this purpose, viz., ethyl cellulose, poly(y-benzyl glutamate), poly(vinyl acetate), cellulose acetate phthalate, and the copolymer of methyl vinyl ether with maleic anhydride. In addition to the base polymers, plasticizers were often needed to impart a suitable degree of flexibility. Plasticizers, which are found to be compatible with polymeric materials include, acetylated monoglycerides, esters of phthalic acid such as dibutyl tartarate, etc. An excipient was usually incorporated into the matrix of the carrier films. The excipients used were water-soluble materials, which are capable of creating channels in the polymer matrix and facilitate diffusion of the drug. PEGs of different molecular weights were used for this purpose. 

Cellulose acetate is incompatible with strongly acidic or alkaline substances. Cellulose acetate is compatible with the following plasticizers diethyl phthalate, polyethylene glycol, triacetin, and triethyl citrate. 

Di(2-methoxyethyl) phthalate n. A plasticizer, especially for cellulose acetate, but compatible, too, with other cellulosics, polystyrene, and vinyls. 

Dimethyl Phthalate n A nontoxic plasticizer for most common thermoplastics, but with limited compatibility with PVC. Plasticizer for nitrocellulose and cellulose acetate, resins, lacquers, plastics. Colorless, odorless, lightfast, stable, nontoxic liquid. Sp gr, 1.189 bp, 282°C fiip, 149°C (300°F). 

PVF resins are generally compatible with phthalate, phosphate, adipate, and dibenzoate plasticizers, and with phenolic, melamine—formaldehyde, urea—formaldehyde, unsaturated polyester, epoxy, polyurethane, and cellulose acetate butylate resins. They are incompatible with polyamide, ethyl cellulose, and poly (vinyl chloride) resins (141). 

The cellulose acetate most suitable for coatings have acetyl contents ranging from about 38 to 40% and a hydroxyl range between 3.0 and 4.0%. The lacquer-type cellulose acetates possess certain fundamental characteristics that have made them difficult to formulate as coatings, yet it is exactly these characteristics that make them valuable in certain areas of the protective coating field. The cellulose acetates are soluble only in very strong solvents (Table IV). They respond well to latent solvents, but they have very low tolerance for hydrocarbons. Compatibility with resins is poor, only a dozen or so commercially available resins are compatible. Only very active plasticizers like dimethyl phthalate, triacetin, or dimethoxyethy1 phthalate will remain in the film without exudation. 

Dimethyl phthalate (DMP) also has high dissolving capacity for CN. It has good compatibility with cellulose esters and are used in celluloid made fi-om CN and plastic compounds or films made from other cellulosic polymers, cellulose acetate (CA), cellulose acetate-butyrate (CAB), cellulose acetate-propionate (CAP), and cellulose propionate (CP). It is light stable but highly volatile. Diethyl phthalate (DEP) possesses properties similar to DMP and is slightly less volatile. 

Diisodecyl adipate (DIDA) n. (-C2H4 COOCioH2i)2. a plasticizer for PVC in lower concentrations, e.g. up to 30 phr, at which it imparts low-temperature flexibility and resistance to lacquer marring. It is often used in combination with phthalate and phosphate plasticizers. DIDA is completely compatible with vinyl chloride-acetate copolymers, cellulose acetate-butyrate with high butyral content, cellulose nitrate, ethyl cellulose, and chlorinated rubber. In polystyrene, it may be used up to 25 phr. 

Di(2-ethylhexyl) isophthalate (dioctyl iso-phthalate, DIOP) n. A primary plasticizer for PVC, most notable for low volatility and its resistance to marring by nitrocellulose lacquers, in addition to good general-purpose properties. It is also compatible with polyvinyl butyral, vinyl chloride-acetate copolymers, cellulosic resins, polystyrene, and chlorinated rubber. 

Plasticisers are also used in products such as lacquers and adhesives that fall outside the definition of the plastics industry. Dicyclohexyl phthalate is used in nitrocellulose lacquers polyethylene glycol and its monostearate are compatible with cellulose nitrate. Dibutyl maleate is compatible with polyvinyl acetate, and di- -hexyl adipate, diethylene glycol di-2-ethyl butyrate or dibutyl sebacate can be used in polyvinyl butyral. Benzoates are recommended for... 

Butyl Ethylhexyl Phthalate n (butyl octyl phthalate, BOP) A mixed ester of butanol and 2-ethylhexanol, widely used as a primary plasticizer for PVC compounds and plastisols, in which it performs like dioctyl phthalate in most respects. It is also compatible with vinyl chloride-acetate copolymers, cellulose nitrate, ethyl cellulose, polystyrene, chlorinated rubber, and at lower concentrations, with polymethyl methacrylate. 

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