Cellulose resin, molding material, molded body, and method for producing cellulose resin

A method for producing a cellulose resin by substituting hydrogen atoms of hydroxy groups of a cellulose with a long-chain component being a linear saturated aliphatic acyl group having 14 or more carbon atoms and a short-chain component being an acyl group (propionyl group) having 3 carbon atoms,

• wherein, in the cellulose resin
• a degree of substitution with the long-chain component (DSLo) and a degree of substitution with the short-chain component (DSSh) satisfy the following conditional expressions (1) and (2):
• 2.1≤DSLo+DSSh≤2.6 (1),
• 4≤DSSh/DSLo≤12 (2),
• DSLo is 0.3 or more,
• the linear saturated aliphatic acyl group is introduced in place of a hydrogen atom of a hydroxy group of the cellulose to form an ester bond,
• the propionyl group is introduced in place of a hydrogen atom of a hydroxy group of the cellulose to form an ester bond,
• Izod impact strength is 5.0 kJ/m2 or more, and
• an MFR (melt flow rate at 200° C. and under a load of 5 kg) is 10 g/10 min or more;
• and
• the method comprises:
• acylating hydroxy groups of a cellulose constituting a pulp by reacting
• the pulp having a polymerization degree of 300 to 700 and dispersed in a solvent with
• propionyl chloride, and
• a long-chain reactant being an acid chloride of a long-chain fatty acid and comprising the long-chain component,
• in the presence of the acid trapping component and under warming, thereby forming an acylated cellulose being the cellulose resin formed by substituting hydrogen atoms of hydroxy groups of a cellulose with the long-chain component and the short-chain component;
• and
• separating the acylated cellulose obtained in the acylating from the solvent,
• wherein the solvent is selected from the group consisting of water, acetic acid, dioxane, pyridine, N-methyl pyrrolidone, N,N-dimethyl acetamide, N,N-dimethylformamide and dimethylsulfoxide, and
• the acid trapping component is selected from the group consisting of an alkaline metal hydroxide, an alkaline earth metal hydroxide, a metal alkoxide, and a nitrogen-containing nucleophilic compound.