title: Molecular weight degradation and rheological properties of schizophyllan under ultrasonic treatment.
abstract: Molecular weight degradation effects of schizophyllan (SPG) under ultrasonic treatments were investigated in this study. The degradation product was treated by alcohol fractional precipitation technology, and the molecular weight and rheological properties of ultrasonic-treated SPG (USPG) fractions were evaluated. Average molecular weight of SPG decreased significantly after ultrasonic treatments, and degradation product had more narrow distribution of molecular weight. The molecular weight degradation kinetics of SPG is adequately described by a second-order reaction. USPG fractions with different molecular weight were obtained by fractional precipitation for final alcohol concentration fractions 0-40%, 40-60% and 60-80%, respectively. USPG fractions had near-Newtonian flow behaviors, and USPG₈₀% exhibited viscous responses over the entire accessible frequency range. Therefore, ultrasonic treatment is a viable modification technology for SPG and other polymer materials with high molecular weight.
authors.affiliation: Institute of Agro-Products Processing Science and Technology, Chinese Academy of Agricultural Sciences, PR China; Key Laboratory of Agro-Products Processing, Ministry of Agriculture, P.O. Box 5109, Beijing 100193, PR China.
authors.forename: Kui
authors.initials: K
authors.lastname: Zhong
authors.affiliation: Institute of Agro-Products Processing Science and Technology, Chinese Academy of Agricultural Sciences, PR China; Key Laboratory of Agro-Products Processing, Ministry of Agriculture, P.O. Box 5109, Beijing 100193, PR China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Institute of Agro-Products Processing Science and Technology, Chinese Academy of Agricultural Sciences, PR China; Key Laboratory of Agro-Products Processing, Ministry of Agriculture, P.O. Box 5109, Beijing 100193, PR China.
authors.forename: Litao
authors.initials: L
authors.lastname: Tong
authors.affiliation: Institute of Agro-Products Processing Science and Technology, Chinese Academy of Agricultural Sciences, PR China; Key Laboratory of Agro-Products Processing, Ministry of Agriculture, P.O. Box 5109, Beijing 100193, PR China.
authors.forename: Liya
authors.initials: L
authors.lastname: Liu
authors.affiliation: Institute of Agro-Products Processing Science and Technology, Chinese Academy of Agricultural Sciences, PR China; Key Laboratory of Agro-Products Processing, Ministry of Agriculture, P.O. Box 5109, Beijing 100193, PR China.
authors.forename: Xianrong
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Institute of Agro-Products Processing Science and Technology, Chinese Academy of Agricultural Sciences, PR China; Key Laboratory of Agro-Products Processing, Ministry of Agriculture, P.O. Box 5109, Beijing 100193, PR China. Electronic address: sumeizhoucaas@gmail.coms.
authors.forename: Sumei
authors.initials: S
authors.lastname: Zhou
mesh_terms: D007700:Kinetics; D008970:Molecular Weight; D012212:Rheology; D012566:Sizofiran / Q000737:chemistry*; D014465:Ultrasonics
chemical_list: D012566:Sizofiran
keywords: Molecular weight degradation; Rheological properties; Schizophyllan; Ultrasonic treatment