THERMAL RESISTANT - BOROSILICATE GLASS
CHARACTERISTICS
- High degree of thermal resistance;
- Low coefficient of thermal expansion
- Low-alkali content
- Free of heavy metals
USES
- Heating open flame or electric heating elements
BRAND EXAMPLES
A. PYREX
Strain point: 515 °C
B. KIMAX
Strain point: 513 °C
OTHER NOTES
- Storing concentrated alkali solutions will etch/destroy the calibration
- Heavy-walled type of glass should not be heated with direct flame or hotplate
- Avoid heating beyond its strain point
ALUMINA-SILICATE GLASS
CHARACTERISTICS
- With aluminum oxide
- Strengthened chemically
- Has greater chemical durability
- More difficult to fabricate
- When coated with an electrically conductive film, can be used as resistors for electronic circuitry
- High impact, extremely strong glass
USES
- Manufacture of calibrated centrifuge tubes;
- touch displays, such as smartphone screens, and for solar cells cover glass and laminated safety glass.
BRAND EXAMPLES
A. COREX (Corning, N.Y.)
- Radiation-resistant;
- 6x stronger than borosilicate;
- Resists clouding and scratching better
For:
a. high precision analytical work
b. optical reflectors and mirrors
OTHER NOTES
- NOT used as general type of glassware in the laboratory
HIGH SILICA GLASS
CHARACTERISTICS
- Silica fused to quartz
- More expensive than borosilicate
- Melted to remove almost all of the non-silicate elements (95-99% silica)
- Very low thermal expansion
- Good chemical durability
- Optical Properties
USES
- Manufacture of spectrophotometer cuvettes, fiber optics, IV-transmissive lamp tubes, precision optics,
refractory tubes
ACID/ALKALI - RESISTANT GLASS
CHARACTERISTICS
- "Soft Glass"
- Boron-free
- Glass with high resistance to acid or alkali
USES
- Used when solutions of strong acids or alkalis are made
BRAND EXAMPLES
A. VYCOR
- Made up of fused silica;
- Heat-resistant and chemically-inert
- Stable to all acids except hydrofluoric types
- Unlikely contamination by contact with solutions
- Relatively inert to acids and neutral salts
- Chlorine and acid gasses does NOT affect the class at any temperature
- Withstand downshocks from 1200-1500 C to ice water
USES: Ashing and ignition technique
LOW ACTINIC GLASS
CHARACTERISTICS
- Usually amber to red color
- Helps to reduce the amount of light transmitted to the substance in the glassware
USES
- Container of light-sensitive substance (bilirubin, vitamin A)
- Store control materials and
- reagents
SODA-LIME GLASS
CHARACTERISTICS
- "Flint Glass"
- Silicon oxide plus:
Soda: sodium oxide Lime: calcium oxide
- Most inexpensive glass
- Readily made into variety types of glassware
- Has high expansion coefficient and
- high degree of thermal resistance
USES
- Manufacture of volumetric flask, stirring rods, single-use pipettes/test tubes
PLASTICWARE
POLYSTYRENE
CHARACTERISTICS
USES
- Rigid
- Clear type
- NOT to be autoclaved
- NOT resistant to most
hydrocarbons, ketones,
and alcohol
- Capped graduated tubes and
test tubes
- Flexible
- Chemical-resistant
- Can be autoclaved
- Micropipette tips
- Especially formulated to
withstand temperature
below -190 °C
- Specimen tubes and test tubes
- May absorb proteins, dyes,
stains and picric acid
- NOT to be autoclaved
- Test tubes
- Bottles
- Graduated tubes
- Stoppers
- Very strong plastic but not
chemically-resistant
- Not suitable for use with strong
acids, bases, and oxidizing agents
- Autoclavable but within limits
- Working temp range:
-100 to 160 °C
- Centrifuge tubes
- Graduated cylinders
- flasks
- Almost chemically-inert
- Chemical-resistant
- Working temp. range:
-73 to 204 °C
- Stirring rods
- Tubing
- Cryogenic vials
- Bottle cap liners
POLYPROPYLENE
POLYETHYLENE
POLYCARBONATE
TEFLON
1 = PET or PETE (polyethylene terephthalate). Soft drink, water, Catsup, salad dressing bottles and others.
2 = HDPE (high density polyethylene). Milk, water, juice, shampoo, detergent bottles.
3 = PVC (polyvinyl chloride). Plastic film wrap, clear food and non-food packaging including some juice
bottles.
4 = LDPE (low density polyethylene). Dry cleaning bags, squeezable bottles like mustard.
5 = PP (polypropylene). Catsup bottles, yogurt containers and margarine tubs, medicine bottles,
6 = PS (polystyrene). Plastic to-go containers, Styrofoam, CD jackets.
7 = Other, or more than one resin used.