Research

Rheology

Rheology team investigates effects of molecular structures, additives, phase separation and large deformation on rheological properties for applying to rheology control in polymer processing. In particular, we focus on non-linear rheology in large deformation.

PP-C wtih a small amount of ultla high molecular weight polyethyrene added to PP-A.

Strain hardening appeared with PP-C.

Fig. Uniaxial elongational viscotsities with several strain artes.

not good.

Good!

Fig. Bottles

Ref. Sugimoto et al., macromolecules, 2001

What's Rheology?

Rheology is the study of deformation and flow within a material.

Rheology around you

CLOTHING---fablic, fiber, plastic fiber
FOOD・・・100% rice bread
SHELTER・・・strength of the structure, sound proofing, viblation control

We can control these things using Rheology!

100% rice bread
100% Rice Bread

Classification of rheology

Polymer Rheology

Rheological properties of the melt or solution of the polymer is affected (including film), the quality of the processing of the elastomer fibers and plastics. Further, the pressure-sensitive adhesive or rheological properties are important properties with the surface chemical.

Dispersion or Suspension Rheology

Printing ink and paint is a typical example, rheological properties are very important for product characteristics .

Bio-Rheology

Field to handle the flow of blood in the blood vessels and rheological properties of blood is referred to as a "hemorrheologic" in particular.

Food Rheology

The rheological sense, such as crisp and crunchy is also an important factor. Ketchup, sauces, mayonnaise, honey, etc.

Electro Rheology

Fluid viscosity changes when you put the electricity.

What is elongational rheology?

Flow behavior is classified into shear flow and elongational flow. Further, elongational flow is classified into uniaxial , biaxial and planar elongational flow, respectively.

Shear elongation

shear

Uniaxial elongation

uniaxial

Equi Biaxial elongation

biaxial

Planar elongation

planar

Key references

M Sugimoto, Y Masubuchi, J Takimoto and K Koyama (2001), Melt Rheology of Polypropylene Containing Small Amounts of High-Molecular-Weight Chain. 2.Uniaxial and Biaxial Extensional Flow. Macromolecules, 34,6056-6063

K Minagawa and K Koyama (2005), Electro- and Magneto-Rheological Materials: Stimuli-Induced Rheological Functions. Current Organic Chemistry, 9, 1643-1663

K Koyama (2005), Control of nonlinear viscoelasticity for polymer melts, Korea-Australia Rheology Journal, 17, 141-143

T Taniguchi, R Uchino, M Sugimoto and K Koyama (2008), Orientation Dynamics of Block Copolymer under an Electric Field, AES Technical Reviews International Journal Part A : International Journal of Nano and Advanced Engineerging Materials, 1, 29-33