Thats Jean Palmieri, new business development manager for Dow Automotive
(Auburn Hills, MI), talking about the cyclic form of polybutylene terephthalate
(CBT) resins. Cyclics Corp. (Schenectady, NY), the company that has developed
the material (actually, it bought the patents on various cyclic compositions from
GE in 1999, and has been subsequently working on developments), and Dow Automotive
have entered into a marketing agreement wherein Dow Automotive is going to be
handling the auto, bus, truck, and rail markets for the plastics.
And when shes talking about this change, she just doesnt mean the
plastics industry. Shes talking about automotive. While there are, at
present, no commercial applications of this new material in any industry, as
she describes it, it becomes quite likely that, as she puts it, the floodgates
will open once there is a wide spread understanding of what it can mean.
Like Water vs. Molasses. OK. Change the industry is a bit much.
Until you comprehend just what the CBT resins actually mean with regard to process
and product. Especially process. When this material melts (it comes in powder,
pellet, and flake forms), it has a low viscosity. Palmieri describes this as
being like water. By way of contrast, she points out that other
thermoplastic materials, when melted, for, say, creating a glass-filled composite
material, have a viscosity like molasses. The CBT flows. It is consequently
capable of moving through molds at comparatively low pressure. She points out
that, for example, if one is trying to make a glass-mat-based composite with
the typical resin, the viscous nature of the material will cause it to get bound
up in the mat and to even push it to places that are not necessarily desirable.
That is not a problem with the CBT. There is said to be excellent wet-out and
the ability to have high filler content. (Polymerization of the material is
based on the use of a catalyst.)
Essentially, the CBT has a low viscosity like a thermoset material, but it
is a thermoplastic. Because of this dual nature, the material can be used in
processes including (but not limited to): compression molding, injection molding,
extrusion, resin transfer molding, and reactive injection molding. Apparently,
theres no need for substantial equipment or tooling changes to occur when
the CBT is used. In fact, Palmieri notes that because of the reduced pressure
involved in molding because of the low viscosity, smaller machines can be used
to make parts. After parts are produced, they can be welded, bonded and painted.
And theyre recyclable (e.g., back to base chemicals or reground for use
as molding compound or as a filler for one). Theres no styrene, so it
is environmentally friendly from that point of view, as well.
Panel Production. Theres another aspect to the processing with CBT that
Palmieri notes: it has a comparatively quick cycle time. Which leads her to
where she thinks the material will really matter in automotive applications:
body panels. She acknowledges that for the most part, there are longer cycle
times associated with making large plastic panels. That has had the effect of
keeping volumes low, perhaps (typically) no more than 75,000 units and as few
as 5,000. But she says that CBT will make it possible to economically compete
with volumes in excess of 150,000 units. She describes injection molding fenders
and quarter panels with 3D geometries that arent limited by compression
molding constraints. She talks about how CBT can be loaded with material
so that it has the toughness, stiffness, and high heat resistance necessary
to be used to produce hoods, deck lids, and roofs. Surface finish? Weve
demonstrated Class A, she replies. Because of the compatibility with so
many filler materials, she points out that the initial application will be Class
B (e.g., truck box components) or non-Class A (e.g., load floors and bumper
beams). We think this will expand the thermoplastic market, she
says.
Plastics producers have long talked about the advantage of comparatively lower
tooling costs for plastic parts as compared with the costs required for steel
or aluminum parts. Palmieri makes the same argument, but is able to point out
that the advantages provided by the lower viscosity makes a tremendous difference
especially as it relates to the equipment required to make larger parts. Then,
she goes on to explain, there are advantages that are based on part characteristics,
such as the modulus stiffness, formability, processability, and weight (i.e.,
you can form shapes with plastics that are difficultperhaps impossibleto
attain with metal, so add to the mix the ability to make these shapes that are
strong and light and to do so quickly, and the plastics vs. metal argument takes
on a whole new aspect).
As there are no commercial parts yet, and as the plant that will be producing
the CBT materials wont come on line until mid-2004, chances are this potential
revolution wont occur in automotive for a few years. But once started,
it could make tremendous changes: think of niche vehicles with their own subniches.