Sökning: "carboxymethyl cellulose"

Visar resultat 1 - 5 av 36 avhandlingar innehållade orden carboxymethyl cellulose.

  1. 1. Microfibrillated cellulose : Energy-efficient preparation techniques and key properties

    Författare :Mikael Ankerfors; Lars Wågberg; Minna Hakkarainen; Paul Gatenholm; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Microfibrillated cellulose; microfibrillar cellulose; nanofibrillated cellulose nanofibrillar cellulose; nanocellulose; MFC; NFC; production techniques; energy efficient; gel properties; films; enzymes; carboxymethylation; carboxymethyl cellulose; CMC; mechanical properties; oxygen barrier; homogenization;

    Sammanfattning : This work describes three alternative processes for producing microfibrillated cellulose (MFC) in which pulp fibres are first pre-treated and then homogenized using a high-pressure homogenizer. In one process, fibre cell wall delamination was facilitated with a combined enzymatic and mechanical pre-treatment. LÄS MER

  3. 2. Microfibrillated cellulose: Energy-efficient preparation techniques and applications in paper

    Författare :Mikael Ankerfors; Lars Wågberg; Akira Isogai; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Microfibrillated cellulose; microfibrillar cellulose; nanofibrillated cellulose; nanofibrillar cellulose; cellulose nanofibrils; nanocellulose; MFC; NFC; CNF; production techniques; energy efficient; gel properties; films; enzymes; carboxymethylation; carboxymethyl cellulose; CMC; mechanical properties; oxygen barrier; homogenization; linting; papermaking; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : This work describes three alternative processes for producing microfibrillated cellulose (MFC; also referred to as cellulose nanofibrils, CNF) in which bleached pulp fibres are first pretreated and then homogenized using a high-pressure homogenizer. In one process, fibre cell wall delamination was facilitated by a combined enzymatic and mechanical pretreatment. LÄS MER

  4. 3. Mercerization and Enzymatic Pretreatment of Cellulose in Dissolving Pulps

    Författare :Heléne Almlöf Ambjörnsson; Ulf Germgård; Thomas Nilsson; Storker Moe; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; alkali; carboxymethyl cellulose; cellulose I; cellulose II; cellulose dissolution; degree of substitution; enzymatic treatment; filterability; gel formation; mercerization; multivariate analytical methods; NIR FT Raman spectroscopy; sodium hydroxide; zink oxide; Chemical Engineering; Kemiteknik;

    Sammanfattning : This thesis deals with the preparation of chemically and/or enzymatically modified cellulose. This modification can be either irreversible or reversible. Irreversible modification is used to prepare cellulose derivatives as end products, whereas reversible modification is used to enhance solubility in the preparation of regenerated cellulose. LÄS MER

  5. 4. Specific ion effects in carboxymethyl cellulose adsorption on cellulose: A step towards modification of fibers in fiber line

    Författare :Vishnu Arumughan; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Carboxymethyl cellulose; Polymer adsorption; Cellulose; Specific ionic effects;

    Sammanfattning : The increasing global demands for paper products have fuelled the research in developing new fibers from existing industrial processes. The adsorption of carboxymethyl cellulose (CMC) has been shown to improve the tensile properties of the paper significantly. LÄS MER

  7. 5. Tailoring Cellulose Nanofibrils for Advanced Materials

    Författare :Núria Butchosa Robles; Qi Zhou; Kristiina Oksman; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cellulose nanofibrils; bacterial cellulose; surface modification; carboxymethyl cellulose; polyethylene glycol; chitin nanocrystals; bactericidal activity; nanofibrils orientation; water redispersability; mechanical properties; dye removal; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Cellulose nanofibrils (CNFs) are nanoscale fibers of high aspect ratio that can be isolated from a wide variety of cellulosic sources, including wood and bacterial cellulose. With high strength despite of their low density, CNFs are a promising renewable building block for the preparation of nanostructured materials and composites. LÄS MER