Podcast Beta
Questions and Answers
Polymers are substances of high molecular weight made up of repeating ______ units.
monomer
The physical and mechanical properties of the polymer can be tailor-made by changing the ______ of the polymer.
composition
Polymers formed from more than one monomer type are called ______.
copolymers
Polymers can be Linear or ______ in structure.
Signup and view all the answers
______ chains have a higher chance of approaching each other in their solid state, which increases their crystallinity and melting temperature.
Signup and view all the answers
Very highly cross-linked polymers are very rigid (three dimensional) structures that degrade at high temperatures before their chains start to ______.
Signup and view all the answers
If a polymer is cross-linked, its ______ will be sacrificed at the expense of swellability.
Signup and view all the answers
Gels are formed when crosslinked polymers are added to ______ (most commonly water).
Signup and view all the answers
Polymers used for preparation of gels are called ______ agents (eg: carbapol)
Signup and view all the answers
Polymers are rarely 100% ______ as it is difficult for all regions of all chains to become aligned
Signup and view all the answers
Polymers can be used as ______ coatings to mask the unpleasant taste of a drugs
Signup and view all the answers
To modify drug release characteristics [controlled release (e.g.extended, pulsatile and targeted) enhanced stability and improved ______
Signup and view all the answers
Inert and compatible with ______ environment
Signup and view all the answers
An example for ______ based technologies in drug delivery
Signup and view all the answers
Study Notes
Introduction to Polymers
- Polymers are substances of high molecular weight made up of repeating monomer units.
- Examples of polymers include proteins (monomer is amino acid) and polysaccharides (monomer is saccharide).
- The word "polymer" means "many parts".
- The physical and mechanical properties of polymers can be tailored-made.
Polymer Categories
- Polymers can be categorized based on composition into homopolymers and copolymers.
- Homopolymers are formed from identical monomeric units, while copolymers are formed from more than one monomer type.
- Polymers can also be categorized based on linkage and structure into linear, branched, cross-linked, crystalline, amorphous, and entangled polymers.
Branched or Linear Polymers
- Polymers can be branched or linear, and branched polymers can form networks of polymers.
- Branched chains can freely move, which offers the polymer a low melting temperature.
- Linear chains have a higher chance of approaching each other in their solid state, which increases their crystallinity and melting temperature.
Polymer Crosslinking
- Linear or branched chains may be joined by crosslinks, which restricts their movement.
- Very highly cross-linked polymers are very rigid (three-dimensional) structures that degrade at high temperatures before their chains start to move.
- If a polymer is cross-linked, its solubility will be sacrificed at the expense of swellability.
Gels
- Gels are formed when crosslinked polymers are added to solvents (most commonly water).
- The polymers do not dissolve in the solvent but instead swell.
- Incorporation of the solvent into the structure of the polymers leads to the formation of the gel.
- Polymers used for preparation of gels are called gelling agents (e.g., carbapol).
Crystalline and Amorphous Polymers
- Polymers are rarely 100% crystalline as it is difficult for all regions of all chains to become aligned.
- Polymers can have both crystalline and amorphous regions.
Pharmaceutical Applications of Polymers
- The pharmaceutical applications of polymers range from their use as binders in tablets to viscosity and flow controlling agents in liquids, suspensions, and emulsions.
- Polymers can be used as film coatings to mask the unpleasant taste of a drug.
- Polymers can enhance drug stability, modify drug release characteristics, and improve bioavailability.
Characteristics of Ideal Polymer System
- Inert and compatible with the environment.
- Nontoxic.
- Easily administrable.
- Easy and inexpensive to fabricate the dosage form.
- Good mechanical strength.
- Example: polymer-based technologies in drug delivery.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Learn about polymers, their composition, and physical properties in Physical Pharmacy. Discover the different categories of polymers and their applications.
