Processes:

Vi-Chem has developed a variety of thermoplastic elastomers (TPE) to meet current and future market needs. These products provide rubber-like properties with thermoplastic processing economics.

We have a variety of engineered PVC Compounds customized for injection molding, extrusion molding, slush molding or blow molding applications.

Injection Molding:
Injection molding is the principal method of forming thermoplastic materials. In this process, plastic material is put into a hopper, which feeds into a heated injection unit. A reciprocating screw pushes the plastic through this long heating chamber, where the material is softened to a fluid state. At the end of this chamber there is a nozzle, which abuts firmly against an opening into a cool, closed mold. The fluid plastic is forced at high pressure through this nozzle into the cold mold. A system of clamps hold the mold halves shut. As soon as the plastic cools to a solid state, the mold opens and the finished plastic is ejected from the press.

Blow Molding:
Blow molding is the process of forming hollow products out of thermoplastic materials by expanding a hot plastic parison (tube of plastic) against the internal surfaces of a chilled mold, using compressed air.

Extrusion:
Extrusion molding is the method employed to form thermoplastic materials into continuous sheeting, film, tubes, rods, profile shapes, and filaments, and to coat wire, cable and cord.

In extrusion, dry plastic material is first loaded into a hopper, then fed into a long heating chamber through which it is moved by the action of a continuously revolving screw. At the end of the heating chamber, the molten plastic is forced out through a small opening or die with the shape desired in the finished product. As the plastic extrusion comes from the die, it is fed onto a conveyor belt where it is cooled, most frequently by blowers or by immersion in water.
In the case of wire and cable coating, the thermoplastic is extruded around a continuing length of wire or cable which, like the plastic, passes through the extruder die. The coated wire is wound on drums after cooling.

In the production of wide film or sheeting, the plastic is extruded in the form of a tube. This tube may be split as it comes from the die and then stretched and thinned to the dimensions desired in the finished film.

Slush Molding:
Slush molding is a process used to form hollow objects with thermoplastic materials. The process involves heating a hollow mold, into which is poured a liquid or powder thermoplastic. The mold is rotated, gelling the plastic to the hot mold. The excess is poured out of the mold, which is then cooled so the finished part can be removed. The mold is then reheated for the next part.
 

Vi-Chem Corporation
55 Cottage Grove Street SW
Grand Rapids, MI 49507-1646 USA

Email: custserv@vichem.com

Phone: (616) 247-8501  ·  Fax: (616) 247-8703  ·  Toll Free: (800) 477-8501