| 摘要 |
A composition comprises a blend of cellulose acetate having a degree of substitution (DS) of greater than 2.1 and an environmentally friendly water soluble plasticizer, preferably selected from the group consisting of citrate based plasticizers, such as triethyl citrate, tributyl citrate or acetyl triethyl citrate; triglycerides such as triacetin or tripropionin; or low molecular weight polyethylene glycols. Preferably the cellulose acetate and plasticizer are both soluble in a solvent such as acetone. Preferably, the plasticizer is included in the material in an amount of up to 25% by weight. Preferably the cellulose acetate has a degree of substitution from 2.1 to 2.8, in particular 2.5. The composition may be prepared by dissolving the cellulose acetate and plasticizer in a solvent to form a single phase after which the solution is cast, moulded or spun. The composition may also be prepared by melting cellulose acetate and blending with the plasticizer to form a homogeneous blend after which the blend is cast, moulded or spun. Preferably, the composition is formed into melt spun or solvent spun fibres which may be formed into a filter for a smoking article, such as a cigarette. Such compositions can, for instance, exhibit an increased rate of degradation compared to conventional, unmodified cellulose acetate. |
