The steps will be familiar to PET processors--blend virgin with regrind,
crystallize, dry, and then extrude sheet--but there are significant differences.
It must be noted that at crystallization temperatures of 180 and 200[degrees]C, which are above the melting temperature of PVDF ([T.sub.m], PVDF = 170[degrees]C), PET can
crystallize without any interference of PVDF crystallization.
In such a ease, the calcium carbonate
crystallizes in a ring shape.
Mantle-melting processes lead to chemical gradation between the two, but under low-pressure conditions in the lithosphere, each basalt type
crystallizes different minerals and evolves in very different ways.
These researchers have identified a double salt of N[a.sub.2]C[O.sub.3] and N[a.sub.2]S[O.sub.4] that
crystallizes in most kraft black liquors.
Instead of presenting the final composition, Zink Yi shows how the salsa is built up from a clave, or basic rhythm, which first
crystallizes in the casual movements of the composer's body before it is played by a band.
[alpha]-TCP
crystallizes in the monoclinic space group [P2.sub.1]/a with a = 12.887(2) [Angstrom], b = 27.280(4) [Angstrom], c = 15.219(2) [Angstrom], [beta] = 126.20(1)[degrees], Z = 24 (33).
Hence, vulcanized NR becomes stiff at low temperature, either because of reduced chain mobility (effect of Tg), or because it
crystallizes. These two effects can be separated by measuring the bending stiffness of a rubber beam at low temperature, as described by ASTM D 797.
Once you get home with your honey, don't be alarmed if it
crystallizes. Many honeys naturally become opaque and hard within days of being harvested; some never do.
In fact, because PBT
crystallizes faster than PET, it is not possible under normal processing conditions to produce PBT parts that are amorphous.
