This document discusses Newtonian and non-Newtonian flow. It begins by introducing rheology and the importance of understanding flow properties for pharmaceutical dosage forms. It then defines Newtonian flow as obeying Newton's law of viscosity and provides examples. Non-Newtonian flow is defined as not following this law and described as existing in three types: plastic, pseudoplastic, and dilatant flow. Specific examples are given for each type of non-Newtonian flow. Rheograms illustrating different fluid behaviors are also included.

1. S.M.B.T COLLEGE OF PHARMACY DHAMANGAON, NASHIK
NEWTONIAN AND NON-NEWTONIAN
FLOW
Presented by:
Ms. Suvarna Shelke
Assistant Professor,
Pharmaceutics Dept.

2. LECTURE OUTCOMES
After completion of this topic students will be
able to-
1. Explain Newtonian flow and Newtonian flow
2. Differentiate between various types of flow
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3. CONTENTS
Introduction
Newtonian flow
Non- Newtonian flow and its types
Summery
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4. INTRODUCTION
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• Rheology is the science that concerns with the flow of liquids and
the deformation of solids.
• Study of flow properties of liquids is important for pharmacist
working in the manufacture of several dosage forms, viz., simple
liquids, gels, ointments, creams, and pastes.
• Types of flow : Newtonian and Non-Newtonian systems.
• These systems changes their flow behavior when exposed to
different stress conditions

5. NEWTONIAN FLOW
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Newtonian Flow
• Liquids that obey Newton’s law of flow
are called as Newtonian fluids.
• Newton’s equation for the flow of
liquids:
F=ηG
• Examples:
Water
Glycerin
Chloroform

6. NON-NEWTONIAN FLOW
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Non-Newtonian Flow
• Non - Newtonian systems are those
substances, which fail to follow Newton's
law.
• Examples: Emulsions, suspensions and
semisolids.
• They are classified into 3 types of flow :
1) Plastic flow
2) Pseudoplastic flow
3) Dilatant flow

7. PLASTIC FLOW
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• The plastic flow curve does not pass
through the origin.
• Material exhibit plastic flow are
called Bingham bodies.
• The equation describing plastic flow
is,
U=F-f/G
• Examples: Flocculated particles in
concentrated suspension, ointments

8. PSEUDOPLASTIC FLOW
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• The consistency curve for a pseudoplastic material
begins at the origin.
• As the shear stress increases progressively , shear
rate also increases, but trend is not linear.
• Also called “Shear thinning system”.
• Examples:
Tragacanth in water, Sodium alginate in water, Methyl
cellulose in water

9. DILATANT FLOW
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• These system exhibit increase in resistance to
flow with increasing rates of shear.
• Dilatant materials also called “Shear
thickening systems.“
• Examples-
Suspension of starch in water, Certain suspensions
with high concentration (50 >%) of small,
deflocculated particles.

10. RHEOGRAMS OF DIFFERENT FLUIDS
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11. SUMMERY
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• In order to be manufactured dosage forms, need specific flow
properties so they can be placed into a container, remain stable
over time, dispensed and handled properly.
• The pouring of the liquids from containers, extrusion of ointment
from tubes, proper application of product to the affected area by
patients these all are depend on the changes in flow behavior of
dosage forms.