Avancerad sökning

Hittade 4 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Wetting and swelling of modified cellulose fibers

    Författare :Fredrik Gellerstedt; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; carboxylic groups; acrylic acid; chemithermomechanical pulps; chemical pulps; pH; succinic anhydride; grafting; esterification; wetting; swelling;

    Sammanfattning : .... LÄS MER

  3. 2. Distributions Of Fiber Characteristics As A Tool To Evaluate Mechanical Pulps

    Författare :Sofia Reyier Österling; Per Engstrand; Hans Höglund; Olof Ferritsius; Rita Ferritsius; Hans Ersson; Per Gradin; Mittuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fiber; fibre; fiber characteristics; fiber dimension; fiber properties; mechanical pulp; FiberLab; raw data; distribution; fiber wall thickness; BIN; bonding ability influence; bonding indicator; bonding ability; fiber width; fibrillation; collapse resistance; laboratory sheet; fiber analyzer; optical analyzer; TMP; CTMP; SGW; sheet model; prediction; fiber characterization; hydrocyclone; fractionation; kernel density estimation; KDE; diffusion mixing; acoustic emission; F0.90; Norway spruce; Picea abies;

    Sammanfattning : Mechanical pulps are used in paper products such as magazine or news grade printing papers or paperboard. Mechanical pulping gives a high yield; nearly everything in the tree except the bark is used in the paper. This means that mechanical pulping consumes much less wood than chemical pulping, especially to produce a unit area of printing surface. LÄS MER

  4. 3. Fenton Pre-treatment of a Birch Kraft Pulp for MFC preparation

    Författare :Pia Hellström; Helena Håkansson; Anette Heijnesson Hultén; Magnus Paulsson; Monica Ek; Karlstads universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Microfibrillated cellulose; Fenton chemistry; carbonyl groups; surface charge; total charge; Enzymatic hydrolysis; Tensile strength; z-directional strength; Chemical Engineering; Kemiteknik;

    Sammanfattning : The potential to use acidic hydrogen peroxide in the presence of ferrous ions (Fenton’s reagent) as a pre-treatment when producing microfibrillar cellulose (MFC) from a fully bleached birch (Betula verucosa) kraft pulp was investigated and the properties of the produced MFC was compared to the properties of a MFC produced with enzymatic pre-treatment with a monocomponent endoglucanase (FiberCare® R). The mechanical treatment to MFC was performed in a laboratory colloid mill or in a pilot high-pressure homogeniser and the pre-treated pulps as well as the produced MFCs were chemically and morphologically characterised. LÄS MER

  5. 4. The influence of fibre characteristics on bulk and strength properties of TMP and CTMP from spruce

    Författare :Niklas Klinga; Mittuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical engineering; Kemiteknik;

    Sammanfattning : This thesis is intended to contribute to an increased knowledge about the influence of fibre characteristics on bulk and strength properties of thermomechanical pulp (TMP) and chemithermomechanical pulp (CTMP) from spruce. It deals with laboratory sheet properties and how they are affected by the conditions during pressing and drying, e.g. LÄS MER