2. Dosage forms (also called unit doses) are pharmaceutical drug products in the form in which they are
marketed for use, with a specific mixture of active ingredients and inactive components (excipients), in a
particular configuration (such as a capsule shell, for example), and apportioned into a particular dose.
For example, two products may both be amoxicillin, but one is in 500 mg capsules and another is in 250
mg chewable tablets.
Depending on the method/route of administration, dosage forms come in several types. These include
many kinds of
1. liquid,
2. solid, and
3. semisolid dosage forms.
Common dosage forms include pill, tablet, or capsule, drink or syrup, and natural or herbal form such as
plant or food of sorts, among many others.
Dosage forms
4. An excipient is a pharmacologically inactive substance formulated alongside the active
pharmaceutical ingredient of a medication.
Purposes served by excipients:
Provide bulk to the formulation.
Facilitate drug absorption or solubility and other pharmacokinetic considerations.
Aid in handling of “API” during manufacturing .
Provide stability and prevent from denaturation
Excipient
6. A list of Pharmaceutical Excipients used in
pharmaceutical preparations
Fillers.
Binders.
Disintegrants.
Coatings.
Sorbents.
Antiadherent.
Lubricants.
Glidants.
Preservatives.
Antioxidants.
Flavoring Agents.
Sweeting Agents.
Coloring Agents.
Solvent & Co-solvent.
Buffering Agents.
Chelating Agents.
Viscosity imparting Agents.
Surface Active Agents.
Humectants .
7. • Fillers:
Fillers typically also fill out the size of a tablet or capsule, making it practical to produce and
convenient for the consumer to use.
Plant cellulose and dibasic calcium phosphate are used popularly as fillers
Function of fillers:
Fillers add volume and/or mass to a drug substance, thereby facilitating precise metering and
handling thereof in the preparation of dosage forms . Used in tablets and capsules.
• Binders:
Binders hold the ingredients in a tablet together . Binders ensure that tablets and granules can be formed
with required mechanical strength, and give volume to low active dose tablets .
Typical features of binders:
A binder should be compatible with other products of formulation and add sufficient cohesion to the
powders .
Examples include gelatin, cellulose, cellulose derivatives, polyvinylpyrrolidone, starch, sucrose and
polyethylene glycol.
8. • Disintigrants:
Disintegrants are substances or mixture of substances added to the drug formulations, which facilitate
dispersion or breakupa of tablets and contents of capsules into smaller particles for quick dissolution when
it comes in contact with water in the GIT
Examples:
polyvinylpyrrolidone , carboxymethyl cellulose, sodium starch glycolate
• Coating Agent:
Coating is a process by which an essentially dry, outer layer of coatinag material is applied to the surface of
a dosage form. Three types of coating agents are used pharmaceutically, Film coating, Sugar coating,
Compression coating.
Examples: HPMC, MC, HPC
• Sorbents:
Sorbents are materials that soak up oil from the water.
Examples:
i. Natural sorbents- peat moss, sawdust, feathers, and anything else natural that contains carbon.
ii. Synthetic sorbents- polyethylene and nylon
9. • Glidants
Glidants are used to promote powder flow by reducing interparticle friction and cohesion. These are used in
combination with lubricants as they have no ability to reduce die wall friction.
Examples include fumed silica, talc, and magnesium carbonate.
• Lubricants
Lubricants prevent ingredients from clumping together and from sticking to the tablet punches or capsule
filling machine. Lubricants also ensure that tablet formation and ejection can occur with low friction between
the solid and die wall.
Examples: Common minerals like talc or silica, and fats, e.g. vegetable stearin, magnesium stearate or stearic
acid are the most frequently used lubricants in tablets or hard gelatin capsules.
Preservatives
Some typical preservatives used in pharmaceutical formulations are:
1) Antioxidants like vitamin A, vitamin E, vitamin C, retinyl palmitate, and selenium
2) The amino acids cysteine and methionine
3) Citric acid and sodium citrate
4) Synthetic preservatives like the parabens: methyl paraben and propyl paraben.
10. Oral liquid dosage forms include solutions, syrups, suspensions, elixirs and concentrates. They offer better
patient compliance in people who find swallowing pills or capsules difficult, and more flexible dosage control
than a fixed-dose tablet.
Oral liquid
11. Creams and ointments contain a different proportion of oil to water. Ointments have a higher concentration of
oil, compared to creams. The more oil, the greasier and stickier the product. Creams may work better on larger
areas of the skin because of their "spreadability" factor, compared to ointments.
Several factors are taken into consideration when selecting a topical product. Skin absorbs a cream more
quickly, whereas an ointment will remain on the skin longer and take a longer time to absorb.
Ointments
An ointment is a homogeneous, viscous, semi-solid preparation, most commonly a greasy, thick oil (oil 80% -
water 20%) with a high viscosity, that is intended for external application to the skin or mucous membranes.
Ointments have a water number that defines the maximum amount of water that it can contain.
12. Granulation, the process of particle enlargement by agglomeration technique, is one of the most
significant unit operations in the production of pharmaceutical dosage forms, mostly tablets and
capsules. Granulation process transforms fine powders into free-flowing, dust-free granules that are
easy to compress.
Granules are produced to enhance the uniformity of the API (active pharmaceutical
ingredient (API) in the final product, to increase the density of the blend so that it occupies less
volume per unit weight for better storage and shipment, to facilitate metering or volumetric
dispensing, to reduce dust during granulation process to reduce toxic exposure and process-related
hazards, and to improve the appearance of the product
Granulation
Techniques
Wet granulation Dry granulation
13.
14. The dry granulation process is used to
form granules without using a liquid
solution because the product granulated
may be sensitive to moisture and heat.
Forming granules without moisture
requires compacting and densifying the
powders. In this process the primary
powder particles are aggregated under
high pressure. Sweying granulator or a
high-shear mixer-granulator can be used
for the dry granulation.
Dry granulation
15. Pneumatic Dry Granulation (PDG)
Pneumatic dry granulation (PDG), an innovative dry granulation technology, utilizes roller compaction
together with a proprietary air classification method to produce granules.
• Granules are produced from powder particles by
initially applying mild compaction force by
roller compactor
• The fine particles and/or smaller granules are
separated from the intended size granules in a
fractioning chamber
• The entrained fine particles and/or small
granules are then transferred to a device such as
a cyclone and are either returned to the roller
compactor for immediate re-processing
(recycling or recirculation process)
• Placed in a container for reprocessing later to
achieve the granules of desired size
16. In wet granulation, granules are formed by the addition of a granulation liquid onto a powder bed which is
under the influence of an impeller (in a high-shear granulator), screws (in a twin screw granulator) or air (in a
fluidized bed granulator). The agitation resulting in the system along with the wetting of the components within
the formulation results in the aggregation of the primary powder particles to produce wet granules
Wet granulation
17. Reverse wet granulation
Reverse wet granulation or reverse-phase wet granulation is a new development in the wet granulation
technique that involves the immersion of the dry powder formulation into the binder liquid followed by
controlled breakage to form granules
18. Steam Granulation
In steam granulation as a new wet granulation technique, water steam is used as binder instead of traditional liquid
water as granulation liquid
19. Moisture-Activated Dry Granulation (MADG)
This technique is a variation of conventional wet granulation technique. It uses very little water to activate a binder and
initiate agglomeration. This technique involves two steps,
1) wet agglomeration of the powder particles, and
2) moisture absorption or distribution.
20. Freeze granulation
Freeze granulation technology, spray freezing and subsequent freeze drying, involves spraying droplets of a
liquid slurry or suspension into liquid nitrogen followed by freeze-drying of the frozen droplets. By spraying a
powder suspension into liquid nitrogen, the drops are instantly frozen into granules.
21. Foam granulation
Foam granulation or foamed binder granulation technology, analogous to spray agglomeration, involves the
addition of liquid/aqueous binder as foam instead of spraying or pouring liquid onto the powder particles.
22. SUSTAINED RELEASE DOSAGE FORMS
Drug delivery systems refer to the technology utilized to present the drug to the desired body site for
drug release and absorption.
IDEAL DRUG DELIVERY SYSTEM should deliver drug at a rate dictated by the needs of the
body over the period of the treatment and it should channel the active entity solely to the site of action.
SUSTAINED RELEASE DRUG DELIVERY is defined as any of the dosage form that maintains
the therapeutic blood or tissue levels of drug by continuous release of medication for a prolonged
period of time, after administration of a single dose.
Sustained release describes the release of drug substance from a dosage form or delivery system over
an extended period of time.
Also referred to as prolonged-release (PR), slow release (SR), sustained action (SA), prolonged action
(PA) or extended-release (ER).
23. 1. SUSTAINED RELEASE DRUG DELIVERY
• Contains loading dose + maintenance dose.
• Loading dose is immediately released to produce quick onset of action.
• Maintenance dose is released at a controlled rate so that the plasma concentration remains
constant above Minimum Effective Concentration (MEC).
• Plasma concentration comes down according to first order elimination kinetics.
2. Delayed release dosage forms
On delayed release dosage forms one or more immediate release units are incorporated into a
single dosage form.
e.g. repeat action tablet, enteric coated tablet.
24. Sustained release dosage
form
• Constitutes dosage form that provides
medication over extended period of time
• SRDF generally do not attain zero order
release kinetics
• Usually do not contain mechanisms to
promote localization of the drug at active
site.
Controlled release dosage
form
• Constitutes dosage form that maintains
constant drug levels in blood or tissue
• Maintains constant drug levels in the blood
target tissue usually by releasing the drug in a
zero order pattern.
• Controlled dosage forms contain methods to
promote localization of the drug at active site.
25. Materials Used in Coating of Sustained Release Dosage Forms (Encapsulation)
Mixtures of waxes [bees wax, carnauba wax, etc] with glyceryl monostearate , stearic
acid , glyceryl mono palmitate and cetyl alcohol.These provide coatings that are
dissolved slowly or broken down in the GIT.
Shellac and zein – polymers that remain intact until the PH of the GI contents become
less acidic
Ethyl cellulose , which provides a membrane around the dosage form and remains intact
throughout the GIT. However, it does permit water to permeate the film, dissolve the
drug , and diffuse out again.
Acrylic resins , which behave similarly to ethyl cellulose as a diffusion controlled drug
release coating material.
Cellulose acetate [di acetate and tri acetate]
Silicone elastomers.
26. Advantages of a controlled drug delivery system
1) Frequency of drug administration is reduced – patient compliance is improved.
2) In multiple dosing of conventional dosage forms the blood level of drug shows oscillatory
characteristic. In controlled release dosage form the blood level is evenly maintained.
3) The safety margin of high potency drugs can be increased and thus side-effects or adverse
effects can be minimized.
4) Total amount of drug administered can be reduced because of maximum utilization.
5) Reduction in health care costs through improved therapy, shorter treatment period, less
frequency of dosing and reduction in personnel time to dispense, administer and monitor
patients.
27. Disadvantages of controlled release dosage forms
1) Decrease systemic availability in comparison to immediate release conventional dosage forms, this
may be due to incomplete release, increased first-pass metabolism, increased instability, insufficient
residence time for complete release site specific absorption, pH dependent solubility etc.
2) Poor in vitro-in vivo correlation.
3) Possibility of dose dumping due to food, physiologic or formulation variables or chewing or oral
formulations by the patient and thus increased risk of toxicity.
4) Retrieval of drug is difficult in case of toxicity, poisoning or hypersensitivity reactions.
5) Reduced potential for dosage adjustment of drugs normally administered in varying strength.
6) Higher cost of formulation.
28. Blood products and therapeutic enzymes
Blood and blood products constitute a major group of traditional biologics. The main components of
blood are the red and white blood cells, along with platelets and the plasma in which these cellular
elements are suspended. Whole blood remains in routine therapeutic use, as do red blood cell and
platelet concentrates.
Major blood products that find therapeutic application
Whole blood
Red blood cells
Platelet concentrate
Plasma and plasma protein fraction
Albumin
Clotting factors (particularly factors VIIa, VIII, IX and XIII)
Haemoglobin
29. Recombinant proteins
1. Insulin
• hormone produced by beta
cells in the pancreas
→ allows glucose to pass into
cells
→ suppresses excess
production of sugar in the liver
and muscles
→ suppresses breakdown of fat
for energy
30. beta cells in pancreas
preproinsulin
proinsulin
insulin + C-peptide
32. Recombinant glycoproteins
2. Interferons
• glycoproteins that “interfere” with viral propagation in
cell cultures
• group of small proteins with 140-170 amino acids
• secretory protein produced from viral-infected cells,
induces antiviral state in neighboring cells
34. 3 main types of interferons:
1. IFN-α (25 subtypes) – produced from β -lymphocytes
2. IFN-β – fibroblasts – produced from fibroblasts
3. IFN-γ – T-lymphocytes – produced from T-lymphocytes
• mode of action not fully understood → synthesis of host enzymes that
degrade viral RNA and inhibit protein synthesis
1. IFN-alpha – uses transformed human cell lines (B-lympphoblastoid cell line),Grow
well in suspension with serum-free medium, first product from a human tumor line
licensed for human therapy- used to treat leukemia
2. IFN-beta – one of the only human interferons that are glycosylated (along with IFN-
a2), higher activity when glycosylated
Ifn-b secreted in response to viral infection or to double stranded RNA
May be used in treatment of tumors, but has short half-life in blood, can’t make it to
tumor
Recombinant forms may be used to fight other diseases, such as multiple sclerosis
(disease of the central immune system, T-lymphocyte breakdown of nerve cells)
3. IFN-gamma – production stimulated by a variety of antigens, most widely used in
staphylococcal enterotoxin A
Anti-tumor effects of IFN-gamma are strongest of the three
35. 5. Erythropoietin (EPO)
• glycoprotein hormone
produced by the kidney
(hypoxia triggers EPO
production)
• required for continuous red
blood cell production in bone
marrow (erythropoiesis)
• absence of EPO results in
impairment of red blood cell
production → anemia
• anemia treated with exogenous
EPO
38. 3. Plasminogen activators
• thrombosis (formation of
blood clots) is a major cause of
premature death
• deposition of fibrin in the
circulatory system, blocks
blood flow
• formation of insoluble fibrin
controlled by clotting cascade
formed during wound healing
• t-PA (tissue-plasminogen
activator) initiates fibrinolysis
(proteolytic cleavage of fibrin)
disulphide bond
N-glycan
40. Factor VIII
• large glycoprotein (265 kDa)
• gene – 186 kB, 26 exons, 25 introns (overlapping strands of DNA
from genomic and cDNA aligned, without introns)
• BHK cells transfected with expression vector containing gene encoding
Factor VIII
4. Blood-clotting factors
• Hemophilia is a sex-linked (x-chromosome) genetic disease
• inactive clotting cascade in blood, can’t form fibrin
→ hemophilia A – absence of factor VIII
→ hemophilia B – absence of factor IX
41. Factor IX
• plasma glycoprotein (57 kDa) secreted by hepatocytes
• called “Christmas factor”, after first family diagnosed with clotting
deficiency
• gene cloned into rat hepatoma cell line
→ contains enzymes for post-translation modifications
• produces biologically active protein with correct tertiary folding and
glycosylation
• stabilized by addition of Willebrand factor, normally found as a combined
protein complex in blood
42. The clotting cascade
Wound surface contact
Factor XII Factor XIIa
Factor XI Factor XIa
Factor IX Factor IXa
+ Factor VIII +
Factor X Factor Xa
Prothrombin Thrombin
Fibrinogen Fibrin clot
+Factor V
Thrombin
43. Analytical methods and test for various drugs and pharmaceuticals
• In the field of pharmaceutical research, the analytical investigation of bulk drug materials,
intermediates, drug products, drug formulations, impurities and degradation products, and
biological samples containing the drugs and their metabolites is very important.
• From the commencement of official pharmaceutical analysis, analytical assay methods
were included in the compendial monographs with the aim to characterize the quality of
bulk drug materials by setting limits of their active ingredient content.
• In recent years, the assay methods in the monographs include titrimetry, spectrometry,
chromatography, and capillary electrophoresis
44. The data in Table 2
based on the edition
of European (The
European
Pharmacopoeia and
Council of Europe,
2002) and US
(United States
Pharmacopoeia,
2004)
pharmacopoeias.
45. Analytical techniques
Titrimetric techniques
Titration, also known as titrimetry, is used to determine the
unknown concentration of an identified analyte. It is also
known as volumetric analysis.
A reagent, called the titrant or titrator is prepared as a standard
solution. A known concentration and volume of titrant reacts
with a solution of analyte or titrand to determine concentration.
Titrimetric methods have been used for the determination of
captopril, albendozole and gabapentin in commercial dosage
forms. Sparfloxacin was determined by the non-aqueous
titration method.
46. Chromatographic technique
1. Thin layer chromatography
Although an old technique yet it finds a lot of application in the
field of pharmaceutical analysis. In thin layer chromatography, a
solid phase, the adsorbent, is coated onto a solid support as a
thin layer usually on a glass, plastic, or aluminum support.
Several factors determine the efficiency of this type of
chromatographic separation. First the adsorbent should show
extreme selectivity toward the substances being separated so as
to the dissimilarities in the rate of elution be large.
TLC has been utilized for the determination of some steroids,
pioglitazone, celecoxib and noscapine.
47. 2. High-performance liquid chromatography (HPLC)
HPLC is an advanced form of liquid chromatography used in separating the complex mixture of
molecules encountered in chemical and biological systems, in order to recognize better the role of
individual molecules.
The specificity of the HPLC method is excellent and simultaneously sufficient precision is also
attainable.
48. 3. Gas chromatography
Moving ahead with another chromatographic technique, gas chromatography is a powerful separation
technique for detection of volatile organic compounds. Combining separation and on-line detection
allows accurate quantitative determination of complex mixtures, including traces of compounds down
to parts per trillions in some specific cases. The creation of high-molecular mass products such as
polypeptides, or thermally unstable antibiotics confines the scope of this technique.
Recently, gas chromatography has been used for assay of drugs such as isotretinion, cocaine and
employed in the determination of residual solvents in betamethasone valerate
49. Spectroscopic techniques
1. Spectrophotometry
Another important group of methods which find an important place in pharmacopoeias are
spectrophotometric methods based on natural UV absorption and chemical reactions. Spectrophotometry is
the quantitative measurement of the reflection or transmission properties of a material as a function of
wavelength.
The use of UV–Vis spectrophotometry especially applied in the analysis of pharmaceutical dosage form has
increased rapidly over the last few years
Ultraviolet and visible (UV-Vis) absorption spectroscopy is the measurement of the attenuation of a beam
of light after it passes through a sample or after reflection from a sample surface. Absorption measurements
can be at a single wavelength or over an extended spectral range.
50. Near infrared spectroscopy (NIRS)
Near-infrared spectroscopy (NIRS) is a spectroscopic method that uses the near-infraredregion of
the electromagnetic spectrum (from about 700 nm to 2500 nm).Near infrared spectroscopy (NIRS) is
a rapid and non-destructive procedure that provides multi component analysis of almost any matrix
51. Fluorimetry and Phosphorimetry
In fluorescence spectrometry both an excitation spectrum
(the light that is absorbed by the sample) and/or an
emission spectrum (the light emitted by the sample) can be
measured. The concentration of the analyte is directly
proportional with the intensity of the emission.
52.
53. A form of fluorimetry in which phosphorescence of a sample is
measured in conjunction with a pulsed source of radiation
Phosphorescence is a type of photoluminescence related to
fluorescence. Unlike fluorescence, phosphorescent material does
not immediately re-emit the radiation it absorbs. The slower
time scales of the re-emission are associated with "forbidden"
energy state transitions
Phosphorimetry
54. INTRODUCTION
• Packaging is the science, art and technology of enclosing or protecting
products for distribution, storage, sale, and use.
• Pharmaceutical packaging can be defined as the economical means of
providing presentation, protection, identification , information, convenience,
compliance , integrity and stability of the product .
FUNCTIONS OF PACKAGING
• Product Identification:- Packaging greatly helps in identification of
products.
• Product Protection:- Packaging protects the contents of a product from
spoilage, breakage, leakage, etc.
• Facilitating the use of product:- Packaging should be convenience to
open, handle and use for the consumers.
• Product Promotion:- Packaging is also used for promotional and
attracting the attention of the people while purchasing.
PHARMACEUTICAL PACKAGING
55. Secondary packaging -
Is outside the primary packaging perhaps used to
group primary package together.
Ex. Boxes, cartons
56. Tertiary packaging- is used to bulk handling and shipping.
Ex. Barrel, container, edge protector
57. TAMPER RESISTANT PACKAGING:
• The requirement for tamper resistant packaging is now one of the major
considerations in the development of packaging for pharmaceutical
products.
• Tamper resistant package is one having an indicator to entry in which, if
missing, can reasonably be expected to provide visible evidence to
consumers that tampering has occurred.
• FDA approves the following configurations as tamper resistant packaging:
Film wrappers, Blister package, Strip package, Bubble pack, Shrink seals,
and bands Oil, paper, plastic pouches, Bottle seals, Tape seals, Breakable
caps, Aerosol containers
58. Film wrapper
Film wrapping has been used extensively over the years for products requiring package integrity or
environmental protection.
It is categorizes into following types:
End folded wrapper
Fin seal wrapper
Shrink wrapper
End folded wrapper
The end folded wrapper is formed by passing the product into a sheet of over wrapping film, which forms the
film around the product and folds the edges in a gift wrap fashion.
The folded areas are sealed by pressing against a heated bar. The materials commonly used for this purpose are
cellophane and polypropylene.
59. Fin seal wrapper
• The seals are formed by crimping the film together and sealing together the two inside surfaces of the
film, producing a fin seal.
• Fin sealing is superior than end folded wrapper With good seal integrity the over wrap can removed or
opened by tearing the wrapper
Shrink wrapper
• The shrink wrap concept involves the packaging of the product in a thermoplastic film that has been
stretched and oriented during its manufacture.
• An L shaped sealer seals the over wrap
• The major advantage of this type of wrapper are the flexibility and low cost of packaging equipment .
60. BLISTER PACKAGE:
Blister package provides excellent environmental protection, and efficacious appearance.
It also provides user functionality in terms of convenience , child resistance and tamper resistance
The blister package is formed by heat softening a sheet of thermoplastic resin and vacuum drawing the
soften sheet of plastic into a contoured mold .
After cooling the sheet is released from the mold and proceeds to the filling station of the machine. It is then
lidded with heat sealable backing material
Peel able backing material is used to meet the requirements of child resistance packaging.
The material such as polyester or paper is used as a component of backing lamination.
Materials commonly used for the thermo formable blister are PVC, polyethylene combinations ,
polystyrene and polypropylene.
61. STRIP PACKAGE
• A strip package is a form of unit dose packaging that is commonly used for the packaging of tablets
and capsule .
• A strip package is formed by feeding two webs of a heat sealable flexible through heated crimping
roller.
• The product is dropped into the pocket formed prior to forming the final set of seals. A continuous
strip of packets is formed in general.
• The strip of packets is cut into desired number of packets.
• Different packaging materials used are: paper/polyethylene/foil/PVC.
62. SEALED TUBES
• Collapsible tubes used for packaging are constructed of metal, plastic or lamination of foil, paper and
plastic.
• Metal tubes are still used for products that required high degree of barrier protection
• . Most of these are made of aluminum .
• Extruded plastic tubes are widely used for products that are compactable and limited protection of
plastic.
BREAKABLE CAPS
Breakable closures come in many different designs.
The roll-on cap design of aluminium shell used for carbonated beverages.
The bottom portion of the cap is rolled around the bottle neck finish.
The lower portion of the cap blank is usually perforated so that it breaks away when the cap is unscrewed.
The bottom portion of the closure has a tear away strip.
63. TYPES OF PACKAGING MATERIALS USED FOR PHARMACEUTICAL
PACKAGING
• Glass
• Plastics
• Rubbers
• Paper/card boards
• Metals
PACKAGE TESTING
• Drop test
• Vibration test
• Shock test
• Inclined impact test
• Revolving drum test
64. GLASS:
Glass has been widely used as a drug packaging material
Advantages
• They are transparent.
• They have good protection power.
• They can be easily labelled.
• Variety of sizes and shapes
Disadvantages
Glass is fragile so easily
broken.
Release alkali to aqueous
preparation
Type I—Highly resistant borosilicate glass
Type II—Treated soda lime glass
Type III—soda lime glass
NP—soda glass (non parenteral usage)
TYPES OF GLASS
65. PLASTIC
Plastics may be defined as any group of substances, of natural or synthetic
origins, consisting chiefly of polymers of high molecular weight that can be
moulded into a shape or form by heat and pressure.
Advantages
Less weight than glass,
flexible
Variety of sizes and shapes
Essentially chemically inert, strong, rigid
Extremely resistant to breakage
Disadvantages
Absorption permeable to
moisture
Poor printing, thermostatic
charge
66. Thermosetting type –
When heated they may become flexible but they do not become liquid
e.g. Urea formaldehyde (UF), Phenol formaldehyde, Melamine formaldehyde (MF), Epoxy resins
(epoxides), Polyurethanes (PURs)
Thermoplastics type-
On heating they are soften to viscous fluid which harden again on cooling.
e.g. Polyethylene {HDPE – LDPE}, Polyvinylchloride (PVC), Polystyrene Polypropylene, Nylon
(PA), Polyethylene terephthalate (PET), Polyvinylidene chloride (PVdC), Polycarbonate
Acrylonitrile butadiene styrene (ABS)
TYPES OF PLASTICS
67. METALS :
Metals are used for construction of containers. The metals commonly used for this purpose are
aluminium ,tin plated steel, stainless steel, tin and lead
Advantages:
• They are impermeable to light, moisture and gases.
• They are made into rigid unbreakable containers by impact extrusion.
• They are light in weight compared to glass containers.
• Labels can printed directly on to their surface.
Disadvantages:
They are expensive.
They react with certain chemicals
68. Tin:
• Tin containers are preferred for food, pharmaceuticals and any product for
which purity is considered.
• Tin is the most chemically inert of all collapsible metal tubes .
Aluminium:
• Aluminium tubes offer significant savings in product shipping costs
because of their light weight .
• They are attractive in nature
Lead:
• Lead has the lowest cost of all tube metals and is widely used for non food
products such as adhesives, inks. paints and lubricants.
• Lead should never be used alone for anything taken internally because of
the risk lead poison .
• With internal linings, lead tubes are used for products such as chloride
toothpaste.
69. RUBBER:
Rubber is used mainly for the construction of closure meant for vials, transfusion fluid
bottles, dropping bottles and as washers in many other types of product.
BUTYL RUBBER:
Advantages:
Permeability to water vapour .
Water absorption is very low.
They are relatively cheaper compared to other synthetic rubbers.
Disadvantages:
Slow decomposition takes place above 130 ▫ C.
Oil and solvent resistance is not very good.
70. SILICON RUBBERS:
Advantages:
• Heat resistance.
• Extremely low absorption and permeability of water.
• Excellent aging characteristic.
Disadvantages:
• They are very expensive.
NITRILE RUBBER:
Advantages : Oil resistant due to polar nitrile group. Heat resistant.
Disadvantages:
Absorption of bactericide and leaching of extractives are considerable.
CHLOROPRENE RUBBERS :
Advantages: Oil resistant. heat stability is good.
