The influence of extended mercerization on some properties of carboxymethyl cellulose (CMC)
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Heléne Almlöf
,
Bjørn Kreutz
Abstract
Carboxymethyl cellulose (CMC) is produced commercially in a two stage process consisting of a mercerization stage in which the pulp is treated with alkali in a water alcohol solution and a second etherification stage whereby monochloro-acetic acid is added to the pulp slurry. In this study, the influence of the conditions of an extended mercerization stage was evaluated on the etherification stage concerning the degree of substitution (DS) and the filterability of the resulting CMC. The parameters studied were: (1) the ratio of cellulose I and cellulose II in the original pulp, (2) the concentration of alkali, (3) the temperature and (4) the retention time in the mercerization stage. The DS results indicate that the NaOH concentration in the mercerization stage is the most important among the parameters studied. When the NaOH concentration in the mercerization stage was high (27.5%), cellulose II showed a lower reactivity than cellulose I with respect to the DS obtained in the resulting CMC. The results from the filtration ability of CMC water solutions are interpreted that the amount of cellulose II in the original pulp and the temperature has a negative influence, while the NaOH concentration in the mercerization stage has a positive influence on the filtration ability. Retention time between 1 h–48 h in the mercerization stage had no effect on the DS or the filtration value. The filtration ability was assumed to be highly influenced by the presence of poorly reacted cellulose segments. The CMC samples with the lowest filtration ability at a given DS can be assumed to have the highest degree of unevenly substituted segments.
©2012 by Walter de Gruyter Berlin Boston
Artikel in diesem Heft
- Original Papers
- Novel paper sizing agents based on renewables. Part 5: characterization of maleated oleates by ozonolysis
- Polythiophene-cellulose composites: synthesis, optical properties and homogeneous oxidative co-polymerization
- The influence of extended mercerization on some properties of carboxymethyl cellulose (CMC)
- Minimizing the effect of undesirable reactions in ECF bleaching
- A rheological description of the water vapour sorption kinetics behaviour of wood invoking a model using a canonical assembly of Kelvin-Voigt elements and a possible link with sorption hysteresis
- Changes in chemistry, color, dimensional stability and fungal resistance of Pinus radiata D. Don wood with oil heat-treatment
- Improvement of dimensional stability of wood via combination treatment: swelling with maleic anhydride and grafting with glycidyl methacrylate and methyl methacrylate
- Synthesis and properties of resol-type phenol-formaldehyde resins prepared from H2SO4- and HCl-catalyzed phenol-liquefied Cryptomeria japonica wood
- Tack and shear strength of hybrid adhesive systems made of phenol-formaldehyde, dextrin and fish glue, and acrylic pressure-sensitive adhesive
- Properties of thermally modified medium-density fibreboards
- Carbonaceous structural changes of wood induced by microwave irradiation
- Development of DNA-based methods to identify CITES-protected timber species: a case study in the Meliaceae family
- Fungal biodegradation of genetically modified and lignin-altered quaking aspen (Populus tremuloides Michx.)
- The effect of fiber dimensions on fiber network activation and tensile strength
- Preparation of chitosan oligomers and characterization: their antifungal activities and decay resistance
- Cellular and topochemical characteristics of secondary changes in bark tissues of beech (Fagus sylvatica)
- Short Notes
- A study by X-ray photoelectron spectroscopy (XPS) of the chemistry of the surface of Scots pine (Pinus sylvestris L.) modified by friction
- Comparative termite resistance of 12 Malaysian timber species in laboratory tests
- Meetings
- 10.1515/HF.2011.185
Artikel in diesem Heft
- Original Papers
- Novel paper sizing agents based on renewables. Part 5: characterization of maleated oleates by ozonolysis
- Polythiophene-cellulose composites: synthesis, optical properties and homogeneous oxidative co-polymerization
- The influence of extended mercerization on some properties of carboxymethyl cellulose (CMC)
- Minimizing the effect of undesirable reactions in ECF bleaching
- A rheological description of the water vapour sorption kinetics behaviour of wood invoking a model using a canonical assembly of Kelvin-Voigt elements and a possible link with sorption hysteresis
- Changes in chemistry, color, dimensional stability and fungal resistance of Pinus radiata D. Don wood with oil heat-treatment
- Improvement of dimensional stability of wood via combination treatment: swelling with maleic anhydride and grafting with glycidyl methacrylate and methyl methacrylate
- Synthesis and properties of resol-type phenol-formaldehyde resins prepared from H2SO4- and HCl-catalyzed phenol-liquefied Cryptomeria japonica wood
- Tack and shear strength of hybrid adhesive systems made of phenol-formaldehyde, dextrin and fish glue, and acrylic pressure-sensitive adhesive
- Properties of thermally modified medium-density fibreboards
- Carbonaceous structural changes of wood induced by microwave irradiation
- Development of DNA-based methods to identify CITES-protected timber species: a case study in the Meliaceae family
- Fungal biodegradation of genetically modified and lignin-altered quaking aspen (Populus tremuloides Michx.)
- The effect of fiber dimensions on fiber network activation and tensile strength
- Preparation of chitosan oligomers and characterization: their antifungal activities and decay resistance
- Cellular and topochemical characteristics of secondary changes in bark tissues of beech (Fagus sylvatica)
- Short Notes
- A study by X-ray photoelectron spectroscopy (XPS) of the chemistry of the surface of Scots pine (Pinus sylvestris L.) modified by friction
- Comparative termite resistance of 12 Malaysian timber species in laboratory tests
- Meetings
- 10.1515/HF.2011.185
