Supermolecular structure of cellulose: stepwise decrease in LODP and particle size of cellulose hydrolyzed after chemical treatment. [Leveling-off degree of polymerization]
It was observed by electron microscopy that rayons hydrolyzed with 2.4 N HCl at 100/sup 0/C for 2 h, followed by ultrasonic treatment were split into homogeneous particles having a size of about 200 A(2000A). In the previous work with rayons, crystallite length, long period, and chain length calculated from their LODP were all about 200 A(2000A), regardless of the type of rayon. The agreement between particle size and length suggested strongly that a rayon microfibril has a periodic structure along its axis at intervals of about A(2000A). Celluloses II, III, and IV and cellulose regenerated from its esters were derived both from native cellulose and rayons in the fibrous state. After hydrolysis, all the modifications derived from native cellulose showed an LODP of about 80 and rod-like fragments which showed a maximum at 400 A(2000A) in the frequency distribution of their lengths. All of the modifications, except mercerized native cellulose, showed a meridional small-angle reflection corresponding to 400 A(2000A). All the modifications from rayons showed an LODP of about 40. The esters derived from native cellulose were recrystallized by heat treatment and then saponified into cellulose II. After hydrolysis, they showed an LODP of about 40 (200 A(2000A) in chain length), a meridional reflection showing a long period of about 200 A(2000A), and a particle-like fragment having a size of about 200 A(2000A). For native cellulose, after chemical and physical treatments, the LODP, the long period, and the fragment length all decreased stepwise and by the same amounts. The steps were an integral multiple of 200 A(2000A), which is the value of the crystallite length obtained for the native and all other celluloses. The results suggest that native cellulose has a periodic structure at intervals of 200 A(2000A) in length. 40 references, 14 figures, 5 tables.
- Research Organization:
- Tokai Univ., Hiratsuka, Japan
- OSTI ID:
- 6856428
- Report Number(s):
- CONF-8205234-Vol.1
- Journal Information:
- J. Appl. Polym. Sci.: Appl. Polym. Symp.; (United States), Journal Name: J. Appl. Polym. Sci.: Appl. Polym. Symp.; (United States); ISSN JPSSD
- Country of Publication:
- United States
- Language:
- English
Similar Records
Supermolecular structures of recrystallized starches with amylopectin side chains modified by amylosucrase to different chain lengths
Effect of the chemical treatments on the characteristics of natural cellulose
Related Subjects
140504 -- Solar Energy Conversion-- Biomass Production & Conversion-- (-1989)
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
ACID HYDROLYSIS
CARBOHYDRATES
CELLULOSE
CELLULOSE ESTERS
CHEMICAL REACTIONS
CHROMATOGRAPHY
COHERENT SCATTERING
CRYSTAL STRUCTURE
DECOMPOSITION
DIFFRACTION
DIMENSIONS
ELECTRON MICROSCOPY
ESTERS
HYDROCHLORIC ACID
HYDROGEN COMPOUNDS
HYDROLYSIS
INORGANIC ACIDS
LENGTH
LYSIS
MATHEMATICAL MODELS
MICROSCOPY
MOLECULAR MODELS
MOLECULAR STRUCTURE
ORGANIC COMPOUNDS
PARTICLE SIZE
POLYMERIZATION
POLYSACCHARIDES
RAYON
SACCHARIDES
SCATTERING
SEPARATION PROCESSES
SIZE
SOLVOLYSIS
X-RAY DIFFRACTION