hemp as a fibre in pharmacy - source, preparation, tests, uses

hemp as a fibre used in pharmacy IV th semester b pharm

1. PLANT FIBRE - HEMPPLANT FIBRE - HEMP

2. Biological Source
Hemp is the pericyclic fibre obtained from
Cannabis sativa Linn., belonging to family
Cannabinaceae.

3. Geographical Source
Hemp is grown at any altitude from Norway
to the Equator.
The raw materials are imported from China,
Hungary, America, Germany, Switzerland,
Australia, Canada, France, and Norway.

4. Cultivation and collection
•The plant is cultivated by sowing the seeds
as kharif crop. Seeds are sowing in June-
July and harvested after six months i.e.,
December- January.
•Plants growing in the tropical countries
(India) produce narcotic substance where
as plant growing in temperate climates
countries do not produces narcotic
substances and it is useful in the production
of fibre and oil.

5. •Due to presence of narcotic substance, it
is cultivated under the government control.
Resinous matter is formed, only in
unfertilized female plant of cannabis.

6. Preparation
•Fibres are obtained by subjecting the
stalks to a series of operations— including
retting, drying, and crushing and a shaking
process that completes separation from
the woody portion, releasing the long,
fairly straight fibre, or line.
•The fibre strands, usually over 1.8 metres
(5.8 feet) long, are made of individual
cylindrical cells with an irregular surface.

7. •Hemp is usually yellowish, greenish, or a
dark brown or gray and, because it is not
easily bleached to sufficiently light shades,
is rarely dyed. It is strong and durable and
is used for rope, cable, and string—and for
artificial sponges

8. Chemical Constituents
Hemp is a cellulosic natural fiber and
cellulose is the main component.
•Cellulose - 77.5%
•Hemicellulose - 10%
•Lignin- 6.8%
• Pectin- 2.9%
• Fat and wax - 0.9%
• Water soluble materials - 1.8%

9. Chemical tests
•Effect of acids - hemp fiber disintegrates on
attack of hot dilute acids or cold concenterated
acids. Hemp fiber is destructed like cotton
fiber in the action of acid.
•Effect of alkalis - hemp fiber is resistant to
alkalis.
•Effect of organic solvents - it is not affected by
organic solvents.
•Ability to dye - it is not suitable to dye the
hemp fiber.

10. Uses
•Hemp is mentioned historically to have
more than 25,000 diverse uses. The
historically mentioned uses are printing
inks, paints, varnishes, paper, bibles, bank
notes, food, textiles, canvas and building
materials.
•Due to its high tensile strength, bast fibres
are ideal for such specialized paper
products as: tea bags, industrial filters,
currency paper, or cigarette paper.