LOW
EXPANSION BOROSILICATE GLASS |
| From 16th century till date, chemical research team
have used glass containers for a basic reason is the
glass containers is transparent, almost invisible and
the contents and the reaction are clear and visible but
to heat, cool and mix chemical substances and ordinary glass is not always enough for laboratory works. |
Laboratory works require apparatus made of glass which can be easily molded into any desired shape
or form. It offers maximum inertness when in contact
with the widest range of chemical substances which can
withstand thermal shock with fracture and high temperature
work without deforming, and that will be resilient enough
to survive everyday knocks to which it will be subjected
in normal laboratory handling, washing and sterilizing
processes. |
Chemical
Composition |
Glassco Glassware is a low alkali borosilicate composition. It is
virtually free of magnesia-lime-Zinc group and contains
only traces of heavy metals. Its typical chemical composition is given below: |
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In general the 'Strain point' should be regarded as
the maximum safe operating temperature of Glassco glassware.
When heated above 500° C the glass may get permanent
stress on cooling. All Glassco lab ware is annealed
in modern ovens under strictly controlled conditions to
ensure minimal residual stress in the products. |
Chemical
Durability |
Glassco Glassware is highly resistance water, neutral
and acid solutions, concentrated on acids and their mixtures
as well as to chloride, bromine, iodine, and organic matters.
Even during extended period of reaction and at temperatures
above 100° C, its chemical resistance exceeds
of mot metals and other materials. It can withstand repeated
dry and wet sterilization without surface deterioration
and subsequent contamination. Resistance to attack of
various chemicals is shown under. Only hydrofluoric acid,
very hot phosphoric acid and alkaline solutions increasingly
attack the glass surface with rising concentration and
temperature. |
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Water distilled at 100°C |
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Water Vapour Steam at
121°C |
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Acid HCI |
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80% H2So4at 130°C |
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Alkali - 1N soln. of NA2Co3
boiling Infusion Fluids Isotonic |
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Nacl(0.85%) 121°C |
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Glucose(5%)121°C |
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Fabrication
with Borosilicate Glass |
Due to low expansion of glass and easy workability
this glass can be shaped, formed, joined into complicated
apparatus. It can be done even by an analyst in his own
laboratory. He can keeps on changing till he gets what
he needs. In case where annealing in a controlled oven
is difficult then he can do so b flame annealing which is also
a great advantage. |
Optical
Properties |
Laboratory glassware is made from Borosilicate Glass which shows
no noticeable absorption in the visible region of the
spectrum. It appear consequently clear and colorless. |
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