Novel cellulose esters derived from the levopimaric acid-maleic anhydride adduct: synthesis, characterization, and properties

• Published in: Cellulose (London) Vol. 24; no. 5; pp. 2029 - 2048
• Main Authors: Bicu, Ioan, Mustata, Fanica
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-05-2017; Springer Nature B.V
• Subjects: Anhydrides; Bioorganic Chemistry; Cellulose; Cellulose esters; Ceramics; Chemical analysis; Chemical industry; Chemistry; Chemistry and Materials Science; Composites; Crystalline cellulose; Cyclohexanone; Esterification; Esters; Glass; Infrared analysis; Infrared spectroscopy; Maleic anhydride; Natural Materials; NMR spectroscopy; Organic Chemistry; Original Paper; Physical Chemistry; Polymer Sciences; Substitution reactions; Sustainable Development; Synthesis; Thermogravimetric analysis; Pyridine; Cellulose ester; Hydrophobicity; Maleated pimaric acid chloride; Esterification
• ISSN: 0969-0239; 1572-882X
• DOI: 10.1007/s10570-017-1243-8

Synthesis of maleated pimaric acid (MPA) cellulose esters is first reported in this work. Cellulose esterification was performed by reacting microcrystalline cellulose with monoacid chloride of MPA (MPA-Cl) in presence of pyridine as catalyst and reaction medium. The syntheses were started in a heterogeneous solid–liquid reaction medium, but as the reaction advanced, the reaction mass turned into a homogeneous solution. The effects of MPA-Cl/anhydroglucose unit molar ratio, reaction temperature, and reaction duration on the yield and degree of substitution (DS) of cellulose esters (CEs) were investigated. CEs with DS ranging from 2.6 to 2.8 were achieved at molar ratios of 5.5–6.0 after 12–16 h at 118 °C. The purified products were characterized by elemental analysis, IR and
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C-NMR spectroscopy, and thermogravimetric analysis. CEs are soluble or partially soluble in usual organic solvents, depending on DS. Transparent films were prepared using CE-cyclohexanone solutions.