Definitions /Dictionary/Glossary - nptel

Moisture Equilibrium: The condition reached by a sample when it no longer takes up moisture
from, or gives up moisture to, the surrounding environment.
Moisture Vapour Transmission: A rate at which water vapour passes through a material at a
specified temperature and relative humidity.
Mold: The cavity or matrix into or on which the plastic composition is placed and from which it
takes form; to shape plastic parts or finished articles by heat and pressure; the assembly of all the
parts that function collectively in the molding process.
Mold Coat: A coat of resin over the bare mold. Used to seal the mold and make a smooth
surface on which to mold parts. This is essentially the same as a gel coat.
Mold Release Agent: A lubricant applied to mold surfaces to facilitate release of the molded
article.
Mold Shrinkage: The immediate shrinkage which a molded part undergoes when it is removed
from a mold and cooled to room temperature; the difference in dimensions, expressed in inches
per inch between a molding and the mold cavity in which it was molded (at normal temperature
measurement); the incremental difference between the dimensions of the molding and the mold
from which it was made, expressed as a percentage of the dimensions of the mold.
Mold Surface: The side of a laminate that faced the mold (tool) during cure in an autoclave.
Molded Edge: It is an edge which is not physically altered after molding for use in final form
and particularly one which does not have fiber ends along its length.
Molding: The forming of a polymer or composite into a solid mass of prescribed shape and size
by the application of pressure and heat.
Molding Compounds: Plastics in a wide range of forms to meet specific processing
requirements. Granules or pellets are popular forms.
Molding Cycle: It is the period of time occupied by the complete sequence of operations on a
molding press requisite for the production of one set of moldings; the operations necessary to
produce a set of moldings without reference to the time taken.
Molding powder or Compound: It is the Plastic material in varying stages of pallets or
granulation. It consisting of resin, filler, pigments, reinforcements and other ingredients ready for
use in the molding operation.
Molding Pressure: It is the pressure applied to the ram of an injection machine (or press) to
force the softened plastic completely to fill the mold cavities.
Molding Pressure, Compression: The unit pressure applied to the molding material in the
mold. The area is calculated from the projected area taken at right angles to the direction of