P. J. Hoftyzer

Bio: P. J. Hoftyzer is an academic researcher from AkzoNobel. The author has contributed to research in topics: Intrinsic viscosity & Polymer. The author has an hindex of 10, co-authored 11 publications receiving 1372 citations.

Newtonian shear viscosity of polymeric melts

Abstract: A new relationship has been found for the Newtonian viscosity of polymeric melts as a function of temperature and of chemical structure of the polymer unit. The viscosity-temperature correlation is expressed graphically. The activation energy of viscous flow at high temperatures can be derived from a newly found additive property, viz. the molar viscosity-temperature function. Es wurde eine neue Beziehung zwischen der Newtonschen Viskositat von Polymerschmelzen und der chemischen Struktur der Polymereinheit gefunden. Die Korrelation zwischen Viskositat und Temperatur wird grafisch dargestellt. Die Aktivierungsenergie der viskosen Stromung bei hohen Temperature last sich aus einer neuen additiven Eigenschaft, der „molaren Viskositats-Temperatur-Funktion”, ableiten.

Prediction of polymer densities

Abstract: A method is proposed for predicting the density of a linear, amorphous polymer. The method is based on the additivity of group increments for the molar volume of a polymer unit. It is analogous to the published methods for predicting the molar volume of organic liquids. The method may be improved as additional experimental values on polymer densities become available.

Hansen Solubility Parameters: A User's Handbook

Abstract: Solubility Parameters - An Introduction C.M. Hansen Hildebrand Parameters and Basic Polymer Solution Thermodynamics Hansen Solubility Parameters Methods and Problems in the Determination of Partial Solubility Parameters Calculation of the Dispersion Solubility Parameter deltad Calculation of the Polar Solubility Parameter deltap Calculation of the Hydrogen Bonding Solubility Parameter deltah Supplementary Calculations And Procedures Hansen Solubility Parameters for Water Theory - The Prigogine Corresponding States Theory, the c12 Interaction Parameter, and the Hansen Solubility Parameters C.M. Hansen Hansen Solubility Parameters (HSP) Resemblance Between Predictions of Hansen Solubility Parameters and Corresponding States Theories The c12Parameter and Hansen Solubility Parameters Comparison of Calculated and Experimental c12 Parameters General Discussion Postscript Statistical Thermodynamic Calculations of the Hydrogen Bonding, Dipolar, and Dispersion Solubility Parameters C. Panayiotou Theory Applications Discussion and Conclusions Appendix I: The Acid Dimerization Appendix II: An Alternative Form of the Polar Term Appendix III: A Group-Contribution Method for the Prediction of delta and deltaD Hansen Solubility Parameters (HSP) in Thermodynamic Models for Polymer Solutions G.M. Kontogeorgis Group Contribution Methods for Estimating Properties of Polymers Activity Coefficients Models Using the HSP Conclusions and Future Challenges Appendix I: An Expression of the FH Model for Multicomponent Mixture Methods of Characterization - Polymers C.M. Hansen Calculation of Polymer HSP Solubility - Examples Swelling - Examples Melting Point Determinations - Effect of Temperature Environmental Stress Cracking Intrinsic Viscosity Measurements Other Measurement Techniques Methods of Characterization - Surfaces C.M. Hansen Hansen Solubility Parameter Correlations with Surface Tension (Surface Free Energy) Method to Evaluate the Cohesion Energy Parameters for Surfaces A Critical View of the Critical Surface Tensions A Critical View of the Wetting Tension Additional Hansen Solubility Parameter Surface Characterizations and Comparisons Self-Stratifying Coatings Maximizing Physical Adhesion Methods of Characterization for Pigments, Fillers, and Fibers C.M. Hansen Methods to Characterize Pigment, Filler, and Fiber Surfaces Discussion - Pigments, Fillers, and Fibers Hansen Solubility Parameter Correlation of Zeta Potential for Blanc Fixe Carbon Fiber Surface Characterization Controlled Adsorption (Self-Assembly) Applications - Coatings and Other Filled Polymer Systems C.M. Hansen Solvents Techniques for Data Treatment Solvents and Surface Phenomena in Coatings (Self-Assembly) Polymer Compatibility Hansen Solubility Parameter Principles Applied to Understanding Other Filled Polymer Systems Hansen Solubility Parameters of Asphalt, Bitumen and Crude Oils P. Redelius Models of Bitumen Asphaltenes Molecular Weight Polarity Solubility Parameters of Bitumen Testing of Bitumen Solubility Hildebrand Solubility Parameters Hansen Solubility Parameters (HSP) The Solubility Sphere Computer Program for Calculation and Plotting of the Hansen 3D Pseudosphere Components of Bitumen Bitumen and Polymers Crude Oil Turbidimetric Titrations BISOM Test Determination of Hansen Solubility Parameter Values for Carbon Dioxide L.L. Williams Methodology One-Component Hildebrand Parameter as a Function of Temperature and Pressure Three-Component (Hansen) Solubility Parameters - Pure CO2 Temperature and Pressure Effects on HSPs: deltad Temperature and Pressure Effects on HSPs: deltap Temperature and Pressure Effects on HSPs: deltah Addendum Appendix I: Ideal Solubility of Gases in Liquids and Published CO2 Solubility Data Use of Hansen Solubility Parameters to Identify Cleaning Applications for "Designer" Solvents J. Durkee A Variety of Solvents Pathology of Soils HSP of Multiple-Component Soils Method for Calculating HSP of Composites (Soils or Solvents) More Realistic View About Evaluating HSP of Composite Soils Method for Choice of Suitable Solvents Reference Soils for Comparison Identification of Designer Solvents An Open Question - Answered Limiting RA Value For Expected Good Cleaning Performance Application of HSP Methodology to Cleaning Operations Analysis of Capability of Designer Solvents Applications - Chemical Resistance C.M. Hansen Chemical Resistance - Acceptable-or-Not Data Effects of Solvent Molecular Size Chemical Resistance - Examples Special Effects with Water Applications - Barrier Polymers C.M. Hansen Concentration-Dependent Diffusion Solubility Parameter Correlations Based on Permeation Phenomena Solubility Parameter Correlation of Polymer Swelling Solubility Parameter Correlation of Permeation Coefficients for Gases General Considerations Applications - Environmental Stress Cracking in Polymers C.M. Hansen ESC Interpreted Using HSP ESC With Nonabsorbing Stress Cracking Initiators Hansen Solubility Parameters - Biological Materials C.M. Hansen and T. Svenstrup Poulsen Hydrophobic Bonding and Hydrophilic Bonding (Self-Association) DNA Cholesterol Lard Human Skin Proteins - Blood Serum and Zein Chlorophyll and Lignin Wood Chemicals and Polymers Urea Water Surface Mobility Chiral Rotation, Hydrogen Bonding, and Nanoengineering Absorption and Diffusion in Polymers C.M. Hansen Steady State Permeation The Diffusion Equation Surface Resistance Side Effects Film Formation by Solvent Evaporation Anomalous Diffusion (Case II, Super Case II) Applications - Safety and Environment C.M. Hansen Substitution Alternative Systems Solvent Formulation And Personal Protection For Least Risk The Danish Mal System - The Fan Selection of Chemical Protective Clothing Uptake of Contents by a Plastic Container Skin Penetration Transport Phenomena The Future Hansen Solubility Parameter Data and Data Quality Group Contribution Methods Polymers as Points - Solvents as Spheres Characterizing Surfaces Materials and Processes Suggested for Further Attention Theoretical Problems Awaiting Future Resolution Appendices Hansen Solubility Parameters for Selected Solvents with the major contribution of Hanno Priebe Hansen Solubility Parameters for Selected Correlations Solubility Data for the Original 33 Polymers and 88 Solvents Index * Each Chapter contains an Abstract, an Introduction, and a Conclusion. Many chapters may also include Acknowledgements, Additional Discussions or General Comments/Considerations, and chapter-specific Key Words, Abbreviations, and Symbols

General strategies for nanoparticle dispersion.

Abstract: Traditionally the dispersion of particles in polymeric materials has proven difficult and frequently results in phase separation and agglomeration. We show that thermodynamically stable dispersion of nanoparticles into a polymeric liquid is enhanced for systems where the radius of gyration of the linear polymer is greater than the radius of the nanoparticle. Dispersed nanoparticles swell the linear polymer chains, resulting in a polymer radius of gyration that grows with the nanoparticle volume fraction. It is proposed that this entropically unfavorable process is offset by an enthalpy gain due to an increase in molecular contacts at dispersed nanoparticle surfaces as compared with the surfaces of phase-separated nanoparticles. Even when the dispersed state is thermodynamically stable, it may be inaccessible unless the correct processing strategy is adopted, which is particularly important for the case of fullerene dispersion into linear polymers.

Properties of Gases and Liquids

Abstract: This chapter is concerned with the properties of gases and liquids (primarily water) relevant to Environmental Physics. Physical properties of gases such as density, heat capacity, and molecular diffusivity influence many of the exchanges between organisms or land surfaces and their environment. Evaporation of water from soils, plants, and animals is also important for their heat balance. Basic equations are developed here to specify the Equation of State of gases and the principles by which the state of liquid water can be specified‘ in organisms and soil. These principles will be applied in later chapters.