Search for dissertations about: "compactibility"

Found 5 swedish dissertations containing the word compactibility.

  1. 1. Improved high velocity cold copaction processing : polymer powder to high performance parts

    Author : Bruska Azhdar; Sture Persson; Cornell Nicolescu; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; high-velocity compaction; powder polymers; polyamide-11; relaxation assist; compactibility; relative green density; morphology; pull-out; springback; Polymer chemistry; Polymerkemi;

    Abstract : A uniaxial High-Velocity Compaction (HVC) process for polymer powder using a cylindrical, hardened steel die and a new technique with relaxation assist was tested with a focus on the compactibility characteristics and surface morphology of the compacted materials using various heights of relaxation assist device with different compacting profiles. Relaxation assist device was presented as a new technique to reduce springback, pull-out phenomenon and to improve the compaction process. READ MORE

  2. 2. Pharmaceutical binders and their function in directly compressed tablets : Mechanistic studies on the effect of dry binders on mechanical strength, pore structure and disintegration of tablets

    Author : Sofia Mattsson; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmacy; Compaction; tablet; binder; pore structure; disintegration; FARMACI; PHARMACY; FARMACI; farmaceutisk farmakologi; Pharmaceutical Pharmacology;

    Abstract : In this thesis, the strength-enhancing mechanisms of dry binders in direct compression were studied. The systems investigated were binary mixtures containing various compounds and binders. Among the binders used were a series of different molecular weights of polyethylene glycol. READ MORE

  3. 3. Novel Technique to Improve High-Velocity Cold Compaction : Processing of Polymer Powders and Polymer-Based Nanocomposite High Performance Components

    Author : Bruska Azhdar; Bengt Stenberg; Leif Kari; Mikael Rigdahl; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polymer powders; nanocomposites; high-velocity compaction; high-energy ball milling; Manufacturing engineering; Produktionsteknik;

    Abstract : Compaction of polymer powders and polymer-based nanocomposites by uniaxial high-velocity cold compaction (HVC), by high-energy ball milling (HEBM) and using a novel technique, relaxation assists, was investigated with a focus on the process parameters, the compactibility characteristics, surface morphology and friction. The basic phenomena associated with HVC are explained and the general energy principle is introduced to explain the pull-out phenomenon, springback gradient, delay time, relative time of the pressure wave, and stick-slip phenomenon during the compaction process. READ MORE

  4. 4. Compression analysis as a tool for technical characterization and classification of pharmaceutical powders

    Author : Josefina Nordström; Göran Alderborn; Maria Strömme; Katharina Picker-Freyer; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; compaction; compression; granules; Kawakita; mechanical properties; particles; PAT; pharmaceutical powders; tablets; Pharmaceutics; Galenisk farmaci;

    Abstract : There are today strong incentives for an increased understanding of material properties and manufacturing processes to facilitate the development of new technologies in the pharmaceutical industry. The purpose of this thesis was to suggest methods requiring a low sample amount for characterization of technical properties of powders. READ MORE

  5. 5. Particle interactions and internal tablet structure : Factors affecting the mechanical strength of pharmaceutical compacts

    Author : Helena Olsson; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmacy; FARMACI; PHARMACY; FARMACI; galenisk farmaci; Pharmaceutics;

    Abstract : A simple tablet model was utilised to identify parameters responsible for tablet compactibility. In this model tablets were considered as homogeneous and isotropic aggregates of individual spherical particles. If the particles were located close enough to each other, interparticulate bonds were assumed to be developed. READ MORE