CATALYTICALLY DEGRADABLE PLASTIC AND USE OF SAME
A catalytically degradable plastic is described, with content of cellulose esters and also optionally of additives. A particular characterizing feature of this catalytically degradable plastic is that it contains a dispersed, catalytically active transition-metal-modified titanium dioxide.
1 - 15 . (canceled)
16 . A catalytically degradable plastics material comprising a catalytically active titanium dioxide modified by addition of at least one transition metal.
17 . The catalytically degradable plastics material as claimed in claim 16 , wherein the plastics material is a cellulose ester, cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, or mixtures thereof.
18 . The catalytically degradable plastics material as claimed in claim 17 , wherein the cellulose ester has an average degree of substitution (DS) of 1.5 to 3.0.
19 . The catalytically degradable plastics material as claimed in claim 17 , wherein the cellulose ester has an average degree of polymerization of 150 to 500.
20 . The catalytically degradable plastics material as claimed in claim 16 , further comprising a finely dispersed non-transition-metal-modified titanium dioxide.
21 . The catalytically degradable plastics material as claimed in claim 16 , wherein the transition-metal-modified titanium dioxide is transition-metal-doped on its surface.
22 . The catalytically degradable plastics material as claimed in claim 16 , wherein the transition-metal-modified titanium dioxide has a crystallite size of 5 to 150 nm.
23 . The catalytically degradable plastics material as claimed in claim 16 , wherein the transition-metal-modified titanium dioxide has a density of 3.0 to 5.0 g/cm 3 , as determined by ISO 787, part 10.
24 . The catalytically degradable plastics material as claimed in claim 16 , wherein the (BET) specific surface area of the transition-metal-modified titanium dioxide is greater than 100 m 2 /g.
25 . The catalytically degradable plastics material as claimed in claim 16 , wherein the transition-metal-modified titanium dioxide has an enhanced light absorption in the range λ≧400 nm compared to pure titanium dioxide.
26 . The catalytically degradable plastics material as claimed in claim 21 , wherein the catalytically degradable plastics material comprises 0.1 to 5 wt % of transition-metal-doped titanium dioxide.
27 . The catalytically degradable plastics material as claimed in claim 16 , wherein the transition-metal-modified titanium dioxide has a transition metal content of from 0.05 to 5 wt %.
28 . The catalytically degradable plastics material as claimed in claim 17 comprising at least 60 wt. % of the cellulose ester.
29 . A molding, fiber, fibers, filter tow, film, films, deep drawn film, deep drawn films, packaging material or materials, injection-molded article or articles, thick-walled molding or moldings, pellets, beads, microbeads, and a vessel or vessels comprising the catalytically degradable plastics material as claimed in claim 16 .
30 . A cigarette filter comprising filter tow, wherein the filter tow comprises the catalytically degradable plastics material as claimed in claim 16 .
31 . The catalytically degradable plastics material as claimed in claim 16 , wherein the material is photocatalytically degradable plastics material.
32 . The catalytically degradable plastics material as claimed in claim 16 , wherein the transition metal is iron.
33 . The catalytically degradable plastics material as claimed in claim 17 , wherein the cellulose ester is cellulose acetate.
34 . The catalytically degradable plastics material as claimed in claim 16 , wherein the transition-metal-modified titanium dioxide has a transition metal content of from 0.3 to 3 wt %.
35 . A process for making a cigarette filter comprising filter plugs, wherein the filter plugs comprise filter tow comprising the catalytically degradable plastics material as claimed in claim 16 .