The present application discloses regioselectively substituted cellulose esters, films made from the regioselectively substituted cellulose esters and methods for making the same. The regioselectively substituted cellulose esters are synthesized using trifluoroacetic anhydride and cellulose with various acyl donors or acyl donor precursors.

The present application discloses regioselectively substituted cellulose esters, films made from the regioselectively substituted cellulose esters and methods for making the same. The regioselectively substituted cellulose esters are synthesized using trifluoroacetic anhydride and cellulose with various acyl donors or acyl donor precursors.

Provided are NCC-based materials, as superb barrier materials for preventing oxygen and humidity from penetrating therethrough.

Provided are NCC-based materials, as superb barrier materials for preventing oxygen and humidity from penetrating therethrough.

A cellulose derivative obtained by substituting at least part of hydrogen atoms of hydroxy groups of a cellulose with an acyl group having 2 to 4 carbon atoms, a long-chain organic group having 7 or more carbon atoms and a high refractive-index organic group.

A cellulose derivative obtained by substituting at least part of hydrogen atoms of hydroxy groups of a cellulose with an acyl group having 2 to 4 carbon atoms, a long-chain organic group having 7 or more carbon atoms and a high refractive-index organic group.

A cellulose ester, wherein, in a structural formula of the following general formula (I), a degree of substitution where X is an acyl group is from 2.91 to 3.0; the acyl group includes benzoyl group (A) optionally having a substituent, and benzoyl group (B) optionally having a substituent different from that of benzoyl group (A); and when the degree of substitution is 3.0, a degree of substitution of benzoyl group (A) is from 1.5 to 2.9, and a degree of substitution of benzoyl group (B) is from 0.1 to 1.5,

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wherein all or some of X represents an acyl group; when some of X represents an acyl group, the remainder represents a group selected from a hydrogen atom and an alkyl group; and n represents an integer of from 20 to 20,000.

A cellulose ester, wherein, in a structural formula of the following general formula (I), a degree of substitution where X is an acyl group is from 2.91 to 3.0; the acyl group includes benzoyl group (A) optionally having a substituent, and benzoyl group (B) optionally having a substituent different from that of benzoyl group (A); and when the degree of substitution is 3.0, a degree of substitution of benzoyl group (A) is from 1.5 to 2.9, and a degree of substitution of benzoyl group (B) is from 0.1 to 1.5,

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wherein all or some of X represents an acyl group; when some of X represents an acyl group, the remainder represents a group selected from a hydrogen atom and an alkyl group; and n represents an integer of from 20 to 20,000.

To provide a cellulose derivative excellent in thermoplasticity, water resistance and strength (elastic modulus, impact strength), a cellulose derivative, which is obtained by introducing a short-chain organic group (acetyl group), a medium-chain organic group having 3 to 5 carbon atoms and a long-chain organic group having 6 to 30 carbon atoms at the following substitution degrees DSs into a cellulose, is used: Short-chain organic group: 0.7≤DS.sub.SH≤1.5; Medium-chain organic group: 0.5≤DS.sub.ME≤2.0; Long-chain organic group: 0.1≤DS.sub.LO<0.5; and 2.4≤DS.sub.SH+DS.sub.ME+DS.sub.LO≤3.

To provide a cellulose derivative excellent in thermoplasticity, water resistance and strength (elastic modulus, impact strength), a cellulose derivative, which is obtained by introducing a short-chain organic group (acetyl group), a medium-chain organic group having 3 to 5 carbon atoms and a long-chain organic group having 6 to 30 carbon atoms at the following substitution degrees DSs into a cellulose, is used: Short-chain organic group: 0.7≤DS.sub.SH≤1.5; Medium-chain organic group: 0.5≤DS.sub.ME≤2.0; Long-chain organic group: 0.1≤DS.sub.LO<0.5; and 2.4≤DS.sub.SH+DS.sub.ME+DS.sub.LO≤3.