POLYMERS
Introduction
The term Polymer derived from the Greek letters ‘Poly’ means many and ‘mers’ means parts. Definition : Polymer is the substance or materials consisting of very large molecules or macromolecules, composed of many repeating subunits, which are known as monomer. These subunits or monomers are typically connected by Covalent chemical bonds.
Classification and types of polymers
Properties of polymer
Advantages & disadvantages
Applications
References
1. POLYMERS
Submitted to
Dr. Vivek Dave Sir
Associate Professor
Head of Department
Department of Pharmacy
School of Health Science
Presented by
Mr. Sree Prakash Pandey
(CUSB2006122010)
M.Pharm 1st year (1st Sem)
Department – Pharmacuetics
School of Health Science
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3. INTRODUCTION
The term Polymer derived from the Greek letters ‘Poly’ means many
and ‘mer’ means parts.
Definition : Polymer is the substance or materials consisting of very
large molecules or macromolecules, composed of many repeating
subunits, which are known as monomer.
These subunits or monomers are typically connected by Covalent
chemical bonds.
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5. Polymers
Based on source
of polymer
Natural
polymers
Semi-synthetics
polymers
Synthetics
polymers
Based on
structure of
Polymer
Linear
polymers
Branch chain
polymers
Cross-linked
polymers
Based on mode
of
Polymerization
Addition
polymerization
Condensation
polymerization
Based on bio-
stability
Bio-degradable
polymers
Non-
biodegradable
polymers
Based on
molecular
forces
Elastomers
Fibres
Thermoplastic
polymers
Thermosetting
polymers
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6. CLASSIFICATION OF POLYMERS
A. Based on source of polymer
1. Natural polymers : These polymers are found in plants and animals.
E.g. proteins, cellulose, starch, resins and rubber.
2. Semi-synthetics polymers : Cellulose derivatives as cellulose acetate
(rayon) and cellulose nitrate.
3. Synthetics polymers : Polythene, Polysterylin, Teflon, Nylon 6,6 and
synthetic rubbers (Buna - S).
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7. B. Based on structure of Polymer
1. Linear polymers : These polymers consist of long and straight chains. e.g.
• high density polythene,
• Polyesters,
• polyvinyl chloride (PVC), etc.
2. Branch chain polymers : These polymers contain linear chains having some
branches, e.g.
• low density polythene,
• Glycogen.
3. Cross-linked polymers : These are usually formed from bi-functional and
tri-functional monomers and contain strong covalent bonds between various
linear polymer chains, e.g
• bakelite,
• melamine,
• vulcanized rubber, etc.
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8. C. Based on mode of Polymerization
1. Addition polymerization : These are formed by the repeated addition of
addition of monomer molecules possessing double or triple bonds. e.g.
polyethene, polypropylene, Polyvinyl chloride, etc.
2. Condensation Polymerization : These are made by combining two
molecules by removing small molecule. e.g. Polyesters, Polyamide,
formaldehyde resins, etc.
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9. D. Based on Bio-stability :
a) Bio-degradable Polymers:
e.g.
• Polylactic acid,
• Polyglycolic acid,
• Proteins,
• Carbohydrates, etc
b) Non – biodegradable Polymers:
e.g.
• Ethyl cellulose,
• Acrylic polymer,
• Poly dimethyl siloxane, etc.
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12. Ideal Characteristics of Polymer
Should be inert and compatible with the
environment.
Should be non-toxic.
Should be easily administered.
Should be easy and inexpensive to fabricate.
Should have good mechanical strength.
Should be biodegradable and biocompatible.
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13. PROPERTIES OF POLYMERS
Molecular weight
Solubility
Viscoelasticity
Tensile strength
Resilience
Percent elongation to break
Crystal nature
Glass Transition Temperature
Tg and the length of the polymer
chain
Tg and polymer chain side group
Tg and polymer chain flexibility
Tg and polymer chain branching
Tg and polymer chain cross-
linking
Tg and processing rate
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14. Advantages
Biodegradable and Biocompatible
Enhance bioavailability
Decrease in dosing frequency
Improve patient compliance
Disadvantages
Exhibit dose dumping effect
Toxicity
High initial drug release after administration
High Processing cost
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15. APPLICATIONS OF POLYMERS
1. APPLICATIONS IN CONVENTIONAL DOSAGE FORMS
Dosages forms Applications Examples
Tablets As binder and
disintegrating agent
HPMC, Starch
Capsules As a Plasticizer Gelatin
Disperse Systems As emulsifying and
suspending agent
PVC, Ethyl cellulose
Gels Gelling agent Gum accasia, sodium
alginate
Skin Patches (TDDS) As a drug reservoir Polystyrene
Film and enteric coating
of Solid Dosage Forms
As a coating agent Chitosan, Cellulose
acetate Phthalate
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16. 2. APPLICATIONS IN CONTROLLED RELEASE DOSAGE FORMS
1. Reservoir Systems
2. Ocusert System
3. Matrix Systems
4. Mucoadhesive drug delivery system
5. Swelling Controlled Release Systems
6. Osmotically controlled Drug Delivery
7. Reservoir Designed Transdermal Patches
8. Temperature Responsive Drug Release
9. pH Responsive Drug Release
10. Electric Current Responsive Drug Release
Some
Pharmacuetical
polymers
Applications
Hydroxypropyl
methyl cellulose
Fabricating hydrophilic
matrix systems
Polyurethane Transdermal patch
backing
Chitosan In hydrogel
Polysorbate 80 Liposomes preparation
Polyamide Gas barrier agent
Carrageenan Viscosifier
Alginic acid Oral and topical
products
Carbapol Trans-corneal
preparations
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17. 3. POLYMERS IN BIOMEDICAL APPLICATIONS
.
Biomedical
Application
1.Cell
delivery
Drug
delivery
Tissue
engineering
Dental
medicine
Skin
treatment
Bone
healing
Wound
healing
Advanced Polymers Application
Polymeric Alginate
(OMIDERM)
Chronic ulcer
Polymeric Foam
(BIOPATCH)
Chronic wound
Polyanhydride Tissue Engineering
Poly(lactic-co-
glycolic) acid (PLGA)
Anticancer therapy
Polyethylene glycol Dentistry
Poloxamers Ophthalmic drug
delivery
Collagens Bone healing
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18. 4. APPLICATIONS FOR DRUG PACKAGING
.
DRUG
PACKAGING
1.Collapsible
tube
1.Rubber cork
1.Bottles and
Vails
1.Plastics and
polybag
Polymers Uses
Polyethylene Collapsible
tubes
Polymeric silicon Rubber Closer
Cyclic Olefin Polymer (COP) Vails
Polyethylene Terephthalate
(PET)
Bottles
LDPE, HDPE, PVC, PET, PP Plastics and
Polybags
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19. 5. GENERAL PHARMACEUTICAL APPLICATIONS
Cosmetic Preparation
Nutritional Application
Increasing drug stability
Pharmaceutical Apparatus and Instruments
Medical Devices and Equipment
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20. REFERENCES
Sinko Patrick J. ; “Martin’s Physical Pharmacy and Pharmaceutical Sciences”; 5th
edition 2005; Lippincott Williams & Wilkins; Page no. 493-515.
Chauhan Narendra P S; “Pharmaceutical Polymers”; January 2014; Research Gate;
Publication 255722509.
Liechty William B.; Kryscio David R.; Slaughter Brandon V.; and Peppas Nicholas
A.; “Polymers of Drug Delivery Systems”; PMC 2012 Sep 11; PMC3438887;
NIHMS402738; PMID22432577.
Patel Jayvandan K., Patel Rakesh P., Amin Avani F., Patel Madhabhai M., and Patel
Shree S.K.; “Formulation and Evaluation of Mucoadhesive Glipizide Microspheres”,
2005 edition.
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