U.S. patent application number 10/954432 was filed with the patent office on 2005-05-05 for multi-layer impact resistant bumper.
This patent application is currently assigned to Boston Metal Products Corporation. Invention is credited to Wallace, James.
Application Number | 20050095413 10/954432 |
Document ID | / |
Family ID | 34555778 |
Filed Date | 2005-05-05 |
United States Patent
Application |
20050095413 |
Kind Code |
A1 |
Wallace, James |
May 5, 2005 |
Multi-layer impact resistant bumper
Abstract
An elongated strip of polymer material having a cross-section
comprising: a first inner core layer of a first polymer material
having a selected configuration along the cross-section of the
strip; a second outer layer of a second polymer material bonded to
an outer surface of the first inner core layer having a second
selected configuration along the cross-section; wherein the first
polymer material has a softness or durometer selected to be
manually bendable and compressible; and wherein the second polymer
material has a durometer or hardness greater than the durometer or
hardness of the first polymer material.
Inventors: |
Wallace, James; (Lynnfield,
MA) |
Correspondence
Address: |
KUDIRKA & JOBSE, LLP
ONE STATE STREET
SUITE 800
BOSTON
MA
02109
US
|
Assignee: |
Boston Metal Products
Corporation
Medford
MA
02155
|
Family ID: |
34555778 |
Appl. No.: |
10/954432 |
Filed: |
September 30, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60508102 |
Oct 2, 2003 |
|
|
|
Current U.S.
Class: |
428/217 ;
264/245; 264/260; 264/299 |
Current CPC
Class: |
F16F 3/093 20130101;
Y10T 428/31928 20150401; B32B 27/304 20130101; B29C 48/304
20190201; B60R 13/04 20130101; B29C 48/11 20190201; B29L 2031/60
20130101; B29C 48/09 20190201; Y10T 428/24983 20150115; B29C 48/21
20190201; B29C 48/25686 20190201; B29C 48/12 20190201; B32B 27/20
20130101; B32B 7/02 20130101; B29C 48/338 20190201; B29C 48/335
20190201; B32B 27/08 20130101; B29C 48/49 20190201; Y10T 428/24008
20150115 |
Class at
Publication: |
428/217 ;
264/245; 264/260; 264/299 |
International
Class: |
B29C 039/20 |
Claims
What is claimed is:
1. An elongated strip of polymer material having a cross-section
comprising: a first inner core layer of a first polymer material
having a selected configuration along the cross-section of the
strip; a second outer layer of a second polymer material bonded to
an outer surface of the first inner core layer having a second
selected configuration along the cross-section; wherein the first
polymer material has a softness or durometer selected to be
manually bendable and compressible; and, wherein the second polymer
material has a durometer greater than the durometer of the first
polymer material.
2. The elongated strip of claim 1 wherein the first and second
layers are co-extruded simultaneously through a die and bonded
during their simultaneous co-extrusion.
3. The elongated strip of claim 2 wherein the second polymer
material comprises a meltable polymer material that is first melted
during the co-extrusion.
4. The elongated strip of claim 2 wherein the first polymer
material comprises a meltable polymer material that has been melted
at least one once prior to the co-extrusion.
5. The elongated strip of claim 1 wherein the second polymer
material contains at least one selected dye.
6. The elongated strip of claim 1 wherein the first polymer
material contains at least two selected dyes.
7. The elongated strip of claim 2 wherein the second polymer
material contains at least one selected dye.
8. The elongated strip of claim 2 wherein the first polymer
material contains at least two selected dyes.
9. The elongated strip of claim 2 wherein the second polymer
material comprises a meltable polymer material that is first melted
during the co-extrusion and wherein the first polymer material
comprises a meltable polymer material that has been melted at least
one once prior to the co-extrusion.
10. The elongated strip of claim 9 wherein the second polymer
material contains at least one selected dye.
11. The elongated strip of claim 9 wherein the first polymer
material contains at least two selected dyes.
12. The elongated strip of claim 1 further comprising a third layer
of a polymeric material bonded to an inner surface of the first
layer.
13. The elongated strip of claim 12 wherein the first, second and
third layers are co-extruded simultaneously through a die and
bonded during their simultaneous co-extrusion.
14. The elongated strip of claim 13 wherein the third layer
comprises a polymeric material that is first melted during the
co-extrusion.
15. An elongated strip of polymer material extruded in an extrusion
cycle having a cross-section comprising: a first inner core layer
of a first polymer material having a selected configuration along
the cross-section of the strip; a second outer layer of a second
polymer material bonded to an outer surface of the first inner core
layer having a second selected configuration along the
cross-section; wherein the second polymer material is first melted
during the extrusion cycle; and, wherein the first polymer material
has been melted at least once prior to the extrusion cycle.
16. The elongated strip of claim 15 wherein the first and second
layers are co-extruded simultaneously through a die and bonded
during the extrusion cycle.
17. The elongated strip of claim 15 wherein the first polymer
material has a softness or durometer selected to be manually
bendable and compressible; and, wherein the second polymer material
has a durometer greater than the durometer of the first polymer
material.
18. The elongated strip of claim 15 wherein the second polymer
material contains at least one selected dye.
19. The elongated strip of claim 15 wherein the first polymer
material contains at least two selected dyes.
20. The elongated strip of claim 17 wherein second polymer material
contains at least one selected dye.
21. The elongated strip of claim 17 wherein the first polymer
material contains at least two selected dyes.
22. The elongated strip of claim 15 further comprising a third
layer of a polymeric material bonded to an inner surface of the
first layer.
23. The elongated strip of claim 22 wherein the first, second and
third layers are co-extruded simultaneously through a die and
bonded during the extrusion cycle.
24. The elongated strip of claim 23 wherein the third layer
comprises a polymeric material that is first melted during the
extrusion cycle.
25. An elongated strip of polymer material extruded in an extrusion
cycle having a cross-section comprising: a first inner core layer
of a first polymer material having a selected configuration along
the cross-section of the strip; a second outer layer of a second
polymer material bonded to an outer surface of the first inner core
layer having a second selected configuration along the
cross-section; wherein the second polymer material contains a dye;
and, wherein the first polymer material contains two or more dyes
and has been melted at least once prior to the extrusion cycle.
26. A method of producing a structural body of two or more layers
of polymeric material, the method comprising: selecting a first
polymer material that has been melted and cooled to solid form;
selecting a second polymer material that has not been melted;
extruding the first and second polymer materials simultaneously in
molten form through a selected mold or die in first and second
strips; layering the simultaneously extruded first and second
strips into contact with each other in their molten form upon
exiting the selected mold or die in a configuration wherein the
first strip is formed has an outer surface and the second strip is
deposited on the outer surface of the first strip.
27. The method of claim 26 wherein the step of selecting the first
polymer material includes selecting a polymer material that
contains a dye material and has been melted.
28. The method of claim 26 wherein the step of selecting the first
polymer material includes selecting a mixture of two or more
polymer materials that have been melted and cooled to solid
form.
29. The method of claim 26 wherein: the step of extruding comprises
forming the first polymeric material upon exiting the mold or die
into a strip form having an outer visible surface and an
undersurface and wherein, the step of layering comprises layering
the second extruded polymer onto the outer visible surface of the
second polymer material.
30. The method of claim 26 wherein: the step of selecting the
second polymer material comprises selecting a predetermined first
polymer material having a first durometer, hardness, bendability or
molecular weight wherein the predetermined polymer material
converts upon melting and cooling to a converted state having a
second durometer, hardness, bendablity or molecular weight that is
less than the first durometer, hardness, bendability or molecular
weight; and wherein, the step of selecting the first polymer
material comprises selecting the predetermined polymer material in
the converted state.
31. The method of claim 26 wherein: the step of selecting the
second polymer material comprises selecting a predetermined second
polymer material; and wherein, the step of selecting the first
polymer material comprises selecting a mixture of two or more
polymer materials each being comprised of the predetermined second
polymer material and each containing a dye.
32. A method of producing a structural body of two or more layers
of polymeric material, the method comprising: selecting a first
polymer material that has been melted and cooled to solid form;
selecting a second polymer material that has not been melted;
extruding the first and second polymer materials simultaneously in
molten form through a selected mold or die in first, second and
third strips; layering the simultaneously extruded first, second
and third strips into contact with each other in their molten form
upon exiting the selected mold or die; wherein the first strip is
comprised of the first polymer material and the second and third
strips are comprised of the second polymer material; and, wherein
the first strip is sandwiched between the second strip and the
third strip.
33. The method of claim 32 wherein: the step of selecting the
second polymer material comprises selecting a predetermined polymer
material having a first durometer, hardness, bendability or
molecular weight wherein the predetermined polymer material
converts upon melting and cooling to a converted state having a
second durometer, hardness, bendablity or molecular weight that is
less than the first durometer, hardness, bendability or molecular
weight; and wherein, the step of selecting the first polymer
material comprises selecting the predetermined polymer material in
the converted state.
34. The method of claim 32 wherein: the step of selecting the
second polymer material comprises selecting a predetermined second
polymer material; and wherein, the step of selecting the first
polymer material comprises selecting a mixture of two or more
polymer materials each being comprised of the predetermined second
polymer material and each containing a dye.
Description
RELATED APPLICATIONS
[0001] This application claims the benefit of priority under 35
U.S.C. Sections 119 and/or 120 to the extent applicable to U.S.
Provisional patent application Ser. No. 60/508,102 filed Oct. 2,
2003 for Multi-Layer Impact Resistant Bumper.
FIELD OF THE INVENTION
[0002] The present invention relates to multilayered products
comprised of polymeric material and methods for producing such
products. More particularly the invention relates to extruded or
molded polymeric material products comprising layers that are
bonded to each other, each layer comprising a polymeric material
having a different selected durometer, hardness, bendability,
impact resistance and/or melting point and/or concentration of dye
and/or plasticizer materials.
BACKGROUND OF THE INVENTION
[0003] Extruded or injection molded products comprising two or more
layers of polymer material are typically produced using complex
molding or extrusion equipment and/or requiring complex processing
steps that are difficult to reproduce from one extrusion or molding
cycle to the next cycle. Processing methods for producing products
comprised of polymer materials are typically developed by trial and
error experimentation with a variety of different polymer materials
having specific properties and molecular weights which, once
determined are specific to production of the desired product and
cannot be varied without substantially changing the end
product.
SUMMARY OF THE INVENTION
[0004] The present invention relates to structural products that
comprise a body of two or more polymer materials adhered or bonded
to each other each polymer material having a different durometer,
hardness, bendability, molecular weight or melting point or
concentration of dye materials and/or plasticizers. The structural
products of the invention are preferably formed as a multi-layered
strip of polymer materials which is/are resistant to impact by
solid objects and/or shock absorbent and resistant to shrinkage
along the longitudinal or axial direction/length of the strip-form
product.
[0005] In accordance with the invention there is provided an
elongated strip of polymer material having a cross-section
comprising:
[0006] a first inner core layer of a first polymer material having
a selected configuration along the cross-section of the strip;
[0007] a second outer layer of a second polymer material bonded to
an outer surface of the first inner core layer having a second
selected configuration along the cross-section;
[0008] wherein the first polymer material has a softness, hardness
or durometer selected to be manually bendable and compressible;
and,
[0009] wherein the second polymer material has a durometer or
hardness greater than the durometer or hardness of the first
polymer material.
[0010] The first and second layers are preferably co-extruded
simultaneously through a die and bonded during their simultaneous
co-extrusion. The second polymer material comprises a meltable
polymer material that is melted for the first time after its
initial manufacture during the co-extrusion. The first polymer
material comprises a meltable polymer material that has been melted
at least one once prior to the co-extrusion. The second polymer
material typically contains at least one selected dye. The first
polymer material typically contains at least two selected dyes.
[0011] The elongated strip may further comprise a third layer of a
polymeric material bonded to an inner surface of the first layer.
In such an embodiment, the first, second and third layers are
co-extruded simultaneously through a die and bonded during their
simultaneous co-extrusion. The third layer typically comprises a
polymeric material that is first melted during the
co-extrusion.
[0012] Further in accordance with the invention there is provided,
an elongated strip of polymer material extruded in an extrusion
cycle having a cross-section comprising:
[0013] a first inner core layer of a first polymer material having
a selected configuration along the cross-section of the strip;
[0014] a second outer layer of a second polymer material bonded to
an outer surface of the first inner core layer having a second
selected configuration along the cross-section;
[0015] wherein the second polymer material is first melted during
the extrusion cycle; and
[0016] wherein the first polymer material has been melted at least
once prior to the extrusion cycle.
[0017] In another aspect of the invention there is provided, a
method of producing a structural body of two or more layers of
polymeric material, the method comprising:
[0018] selecting a first polymer material that has been melted and
cooled to solid form;
[0019] selecting a second polymer material that has not been
melted;
[0020] extruding the first and second polymer materials
simultaneously in molten form through a selected mold or die in
first and second strips;
[0021] layering the simultaneously extruded first and second strips
into contact with each other in their molten form upon exiting the
selected mold or die in a configuration wherein the first strip as
formed has an outer surface and the second strip is deposited on
the outer surface of the first strip.
[0022] The step of selecting the first polymer material includes
selecting a polymer material that contains a dye material and has
been melted prior to the step of extruding and most preferably
comprises selecting a mixture of two or more polymer materials that
have been melted and cooled to solid form.
[0023] The step of extruding typically comprises forming the first
polymeric material upon exiting the mold or die into a strip form
having an outer visible surface and an undersurface wherein, the
step of layering comprises layering the second extruded polymer
onto the outer visible surface of the second polymer material.
[0024] The step of selecting the second polymer material typically
comprises selecting a predetermined first polymer material having a
first durometer, hardness, bendability or molecular weight wherein
the predetermined polymer material converts upon melting and
cooling to a converted state having a second durometer, hardness,
bendability or molecular weight that is less than the first
durometer, hardness, bendability or molecular weight; and wherein
the step of selecting the first polymer material comprises
selecting the predetermined polymer material in the converted
state.
[0025] The step of selecting the second polymer material may
comprise selecting a predetermined second polymer material and the
step of selecting the first polymer material may comprise selecting
a mixture of two or more polymer materials each being comprised of
the predetermined second polymer material and each containing a
dye. In another aspect of the invention there is provided, a method
of producing a structural body of two or more layers of polymeric
material, the method comprising: selecting a first polymer material
that has been melted and cooled to solid form;
[0026] selecting a second polymer material that has not been
melted;
[0027] extruding the first and second polymer materials
simultaneously in molten form through a selected mold or die into
first, second and third strips;
[0028] layering the simultaneously extruded first, second and third
strips into contact with each other in their molten form upon
exiting the selected mold or die;
[0029] wherein the first strip is comprised of the first polymer
material and the second and third strips are comprised of the
second polymer material; and;
[0030] wherein the first strip is sandwiched between the second
strip and the third strip.
[0031] In such an embodiment, the step of selecting the second
polymer material may comprise selecting a predetermined polymer
material having a first durometer, hardness, bendability or
molecular weight wherein the predetermined polymer material
converts upon melting and cooling to a converted state having a
second durometer, hardness, bendablity or molecular weight that is
less than the first durometer, hardness, bendability or molecular
weight; and wherein the step of selecting the first polymer
material may comprise selecting the predetermined polymer material
in the converted state.
[0032] The step of selecting the second polymer material may
comprise selecting a predetermined second polymer material wherein
the step of selecting the first polymer material may comprise
selecting a mixture of two or more polymer materials each being
comprised of the predetermined second polymer material and each
containing a dye.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 is an underside/perspective cross sectional view of a
composite material extruded bumper product according to the
invention showing a solid strip form extruded body of material
comprising a top outer layer of relatively hard polymer material,
an inner or intermediate layer of relatively soft or less hard and
more bendable polymer material and an undersurface strip of
relatively hard, shrink resistant polymer material;
[0034] FIG. 2 is a topside/perspective cross sectional view of the
Fig. product showing the product mounted or snap fit onto a
railing;
[0035] FIG. 3 is a schematic cross sectional view of the FIG. 1
product;
[0036] FIG. 4 is a rear elevational view of the first plate as seen
along line 4-4 of FIG. 3;
[0037] FIG. 5 is a rear elevational view of the second plate as
seen along line 5-5 of FIG. 3;
[0038] FIG. 6 is a rear elevational view of the third plate as seen
along line 6-6 of FIG. 3;
[0039] FIG. 7 is a rear elevational view of the fourth plate as
seen along line 7-7 of FIG. 3;
[0040] FIG. 8 is a front elevational view of the fourth plate as
seen along line 8-8 of FIG. 3;
[0041] FIG. 9 is a front cross-sectional view of the FIG. 1
product; and,
[0042] FIG. 10 is an exploded perspective view of the third and
fourth plates shown in FIG. 3.
DETAILED DESCRIPTION
[0043] FIGS. 1, 2 and 9 show an extruded length of a multi-strip
formed bumper product 8 comprising an outer facing strip 10 of
relatively hard polymer material, and intermediate strip 20 of
relatively soft, rubbery or bendable polymer material and an
undersurface strip 40 of relatively hard, rigid, shrink resistant
polymer material. The outer coat or strip component/layer 10 is
bonded during the extrusion process, preferably immediately upon
exit from the final extrusion die, to the outer surface of the
inner soft or manually bendable layer or strip 20 such that the end
product assumes the outward visual appearance of a relatively hard,
shiny surface as opposed to the inner layer 20 which cannot be
visually seen when mounted on a rail 30 as shown in FIG. 2.
[0044] FIG. 2 shows the elongated strip-like product 8 mounted on a
rigid, inflexible metal rail 30 by snap fitting of preformed
tongues or detents 55 formed on the underside 57, FIG. 1, of the
core 20 strip/layer onto a complementary receiving set of grooves
or detents 59 formed on the outside surface the rail 30 shown in
FIG. 2.
[0045] As shown in FIG. 3, the composite material feed for the core
20 is fed directly from the exit barrel 6 of the extruder through a
central composite material bore 50 that extends through each of
plates 1-4. The polymer feed for the cap coat 10 is fed through an
aperture 60 extending from the exit side to the entrance side of
plate 4 through plate 4, the feed then being routed through a bore
70, FIGS. 7, 8, 10 on the entrance side of plate 4 such that the
cap coat material feed is ultimately routed through plate 4 and out
the exit side of bore 70 on the exit side of plate 4, FIGS. 7, 8,
10 simultaneously with the extrusion of the feed material for the
core 20 being routed through central bore 50. The polymer feed for
the rigid non-shrink strip 40 is initially fed through an aperture
80 extending from the exit side to the entrance side of plate 4
through plate 4, the feed then being routed through a groove 90,
FIGS. 7, 8, on the entrance side of plate 4 such that the rigid
strip 40 material is ultimately routed through plate 4 and out the
exit side of bore 100 on the exit side of plate 4 simultaneously
with the extrusion of the feed material for the core 20 being
routed through central bore 50 and the feed material for the cap
coat 10 being routed through bore 70. Thus all three separate
streams of polymer materials comprising the cap coat 10, core 20
and rigid undersurface strip 40 are simultaneously co-extruded and
come into contact with each other in a molten state immediately
upon exit from the exit side of plate 4. Once the three co-extruded
streams of materials come into contact with each other in the
molten state, the materials firmly bond to each other during and
upon cooling to form the product shown in FIGS. 1, 2, 9.
[0046] FIG. 3 shows an additional end plate 5 that may be used
together with the plates 1-4 assembly, the exact configuration and
use of plates and equipment to effect the fluid material feed
connections to the bores of plates 1-4 being a matter of design
choice for the skilled artisan. The disclosed embodiment showing
the use of four separate plates 1-4 is shown for purposes of
example only. Any number or configuration of extrusion plates that
achieve the function of routing of the thermoplastic polymer
materials as shown may be used in the process. Positioning the exit
ends of feed bores 50, 70, 80 in close adjacency to each other such
that the separate streams of exiting polymer materials contact the
surfaces of each other upon exit from the extrusion plates is most
preferred so that the separate streams of exiting polymer materials
come into contact with each other in a molten state immediately
upon exit and thereby adhere to each other upon cooling from the
molten state to a stable cooled state. When the separate streams of
polymer materials come into contact with each other in the molten
state the mating surfaces mix together somewhat at the point of
contact and upon cooling to a crystalline state become essentially
adhered to each other to form a the unitary product 8 shown in
FIGS. 1, 2, 9. The separate streams of extruded polymer materials
may alternatively be bonded to each other with a bonding
material.
[0047] FIGS. 3, 10 show a solid rod or wire 200 that may be
positioned through the end portion of bore 50 in the middle of the
detent 55 configuration of the core 20 strip to enable an elongated
aperture 25 to be formed within the body of the detent during the
extrusion process to impart additional bendability or flexibility
to the detent 55. Such additional flexibility imparted to the
detent 55 better enables the detent to be manually snap fit around
or over the outer surface of the complementary protrusion or detent
59 of the rail 30 onto which the bumper strip 8 is mounted. The
snap fitted mounting of detents 55 onto the protrusions 59 firmly
holds the bumper 8 on the rail 30.
[0048] The core material 20 typically comprises a mixture of
polymer materials that have been previously processed and melted in
a prior extrusion or injection molding cycle, e.g. a mixture of
scrap materials from previous extrusion cycle runs of one or more
selected thermoplastic polymer materials such as polyvinyl chloride
(PVC) where each scrap material contains a different
concentration/amount of dye material and/or a different durometer
or hardness. The subsequent extrusion processing cycle carried out
on previously extruded or molded materials causes the composite
material now being melted a second time in the course of an
extrusion or molding process to assume a lower durometer than the
originally extruded product comprising virgin material and/or a
greater rubberiness, flexibility or bendability than the original
virgin material. The lower durometer of scrap material may also be
a result of the scrap materials containing several different dye
and other additives such as plasticizers and the like.
[0049] As used herein the phrase "melted for the first time" or
"first melted" or the like means that the polymer material has not
been previously melted during an extrusion or molding process, it
being understood that the starting polymer material may have been
previously in a molten form as a result of its having been
produced/manufactured in the first instance.
[0050] The cap coat 10 thermoplastic material selected is
preferably virgin polymer material that has not been previously
extruded or otherwise melted and typically does not initially
contain a dye. The cap coat 10 material upon extrusion has a higher
durometer, rigidity and less rubberiness, flexibility and
bendability than the core material 20. One or more dye materials
that comprise between about 3% and about 10%, e.g. 4-7%, by weight
of the cap coat polymer material may be mixed with/added to the
thermoplastic starting feed material for the cap coat 10.
[0051] The non-shrink strip material 40 is also preferably
comprised of a virgin polymer material that has not been previously
extruded or otherwise melted. Most preferably, the non-shrink strip
material is the most rigid of the three polymer materials and is
the most resistant to shrinkage particularly in/along the
longitudinal direction of the elongated strip-form product 8. The
non-shrink material may comprise the same or substantially the same
virgin polymer material as the core 20 material. The rigid strip 40
provides a particular resistance to shrinkage of the core material
20 along the longitudinal or axial length of the elongated extruded
strip-like product 8 by virtue of being bonded to the underside of
the core 20 strip. Such resistance to shrinkage by virtue of the
bonding of the non-shrink strip 40 to the core strip component 20
thus obviates the necessity for replacing edge, end or corner
pieces that are typically attached to or mounted at the ends of a
finished strip product 8 once installed on a rail 30 in an actual
shelf, counter or other retail store environment.
[0052] The polymer material selected for use in comprising the cap
coat 10 and the core 20 typically comprises the similar basic
polymers, mixture of polymers or thermoplastic materials, e.g.
thermoplastic polyvinyl chlorides, nylons, polyesters, polyethers,
polyamides, rubbers and latex rubber materials and copolymers of
one or more of all of the foregoing. That is the polymer materials
of which the cap coat 10 and the core 20 are comprised typically
have essentially the same units making up the polymer backbone. The
polymer material of the cap coat 10 and core 20 materials typically
differ somewhat in polymer chain length, degree of cross
polymerization (if any) or in concentration and composition of dye
materials contained within the matrix of the materials. For
example, the virgin cap coat 10 material typically comprises a
polymer material having a durometer of between about 75 and 90,
e.g. 80-85, and the core layer 20 material comprises a mixture of
two or more scrap materials that were originally extruded from the
same basic material as the cap coat 10 material containing the same
or different dye materials at the same or different concentrations
as the cap coat 10 material contains.
[0053] Polymer materials suitable for use in the invention are
thermoplastic polymers that are relatively pliable or manually
bendable such as polyvinyl chloride, polyamide, polyether,
polyester and copolymers of all of the foregoing with one or more
of each other or with urethane or other polymer units that impart a
suitable manual bendability to the end polymer. Stiffeners,
plasiticizers, catalysts and the like may be contained within the
polymer materials to impart any desired degree of flexural modulus,
hardness, impact resistance and like mechanical/physical properties
to the polymer material.
* * * * *