Note: Descriptions are shown in the official language in which they were submitted.
1263~9:3
-1- 24133-613D
SMALL PARTICLE SIZE HYDRATED ALUMINA
AS AN IMPACT SYNERGIST FOR IMPACT
MODIFIED VINYL HALIDE POLYMERS
BACKGROUND OF THE INVENTION
This divisional application is divided out of parent
application serial No. 415,883 filed on November 18, 1982.
The invention of the divisional and parent applications
is directed to polymeric vinyl halide formulations and more part-
icularly to the use of very fine particle size (less than about
1~ avg.) hydrated alumina to form a synergistic combination with
impact modifiers or fillers in polymeric vinyl halide formulat-
ions, preferably rigid formulations.
This divisional application is directed to combinations
with impact modifiers, while the parent application is directed
to combinations with fillers.
Generally, the most commercially important polymeric
vinyl halide material is polyvinyl chloride (PVC) and this inven-
tion will be described herein in terms of PVC. However, it is
to be understood that it is applicable to other polymeric vinyl
halide materials, as hereinafter defined.
Fillers are added to polymeric vinyl halide materials
primarily to reduce cost and, when used in low concentrations,
to provide a scrubbing action and reduce plateout. Generally,
when their concentration is high enough to affect physical proper-
ties, they increase modulus, decrease tensile strength and elon-
gation, and usually decrease impact strength. There are a few
~;2~3'-~93
-la- 24133-613D
fillers, such as fine particle size precipitated, hydrated
silicas and ultra-fine, precipitated, coated calcium carbonates
that maintain, and even enhance, irnpact strength in rigid PVC
formulations [J. Radosta, 37th ~PE Annual Technical Conference
Preprints, pg. 593 (1979)]. These fillers have not gained wide
use in
-- 12~3~93 ~
--2--
exterior rigid PVC applications because of their adverse
effect on weatherability.
Hydrated alumina has been gaining acceptance as an
additive for use in plastic parts, its low cost along with
5 its flame-retardant and smoke-suppressing characteristics
being most widely referred to in the literature (J. Z.
Keating, Plastics Compounding, pg. 23, July/August, 1980).
Most reported uses of hydrated alumina in PVC compounds have
been generally limited to plasticized compositions where
lO improved flame retardancy is obtained when used in
concentrations greater than about 10 parts per hundred of
polymer [A. W. Morgan, T. C. Mathis and J. D. Hirchen, 30th
SPE Annual Technical Conference Preprints, Chicago, pg. 475
(1972); R. W. Sprague, "Systematic Study of Firebrake ZB as
15 a Fire Retardant in PVC - Part IV Alumina Trihydrate as a
Synergist", April, 1973, January, 1975, U. S. Borax Research
Corporation, Anaheim, California; C. E. Hoke, ~PE Journal,
29 pg. 36 (May, 19733], but I. Sobolev and E. A. Woychesin,
SPE Annual Technical Conference Preprints, pg. 709 (1973)
20 report the use of a 40~ loading of hydrated alumina in a
rigid PVC formula as a smoke suppressant and show that the
filler did not reduce the impact strength. Further, it has
recently been suggested, for example, in U. S. Patent
3,957,723 to Lawson et al U.S. Patent 3,985,706 to Kay, U.S.
25 Patent 4,143,030 to Hartitz, and U.S. Patent 4,147,690 to
Rich, that improved flame retardancy and smo~e suppression
can be achieved by a synergistic combination of alumina
trihydrate with zinc oxide, zinc borate or bizmuth
subcarbonate.
It has now been found that extremely fine particle size
(less than l~u) hydrated alumina can not only be used as an
~2637'93
-3- 24133-613D
additive for PVC which does not reduce the impact strength of the
material, but unexpectedly shows a high degree of synergism with
conventional impact modifiers to give significant increases in
impact strength accompanied by improved processibility and weather-
ing,
Hydrated alumina has often been called alumina hydrate
or alumina trihydrate. The empirical formula is s ~ times written
A1203.3H20 because at elevated temperature, it functions as a
flame retardant by decomposing to aluminum oxide and water. But
this formula is technically incorrect. The product is actually
finely divided crystalline aluminum hydroxide with the composit-
ion Al (OH)3.
SUMMARY OF THE INVENTION
Very fine particle size (less than about 1~ avg.)
hydrated alumina is useful as a filler material in polymeric
vinyl halide materials, and when used in combination with impact
modifiers ~r fillers, act synergistically to enhance the impact
strength of the PVC materials.
According to one aspect of the invention of the parent
application there is provided a polymeric vinyl halide composit-
ion having improved weatherability and processing characterist-
ics which consist essentially of a polymeric vinyl halide material,
a filler material and up to 24 phr of hydrated alumina having
an average particle size less than 1~.
~a -
24133-613D
In accordance with the invention of the present
divisional application there is provided a method for increasing
the impact resistance of a polymeric vinyl halide material which
comprises incorporating in a polymeric vinyl halide material an
amount of an impact modifier which is a synthetic high molecular
weight polymeric rubbery material and of hydrated alumina having
an average particle size less than about 1~ which forms a
synergistic combination for increasing the impact resistance of
said polyvinyl halide material.
In accordance with the invention of the parent applica-
tion there is also provided polymeric vinyl halide compositions
having improved weatherability and processing characteristics,
comprising a polyvinyl chloride polymer or copolymer, a filler
material
~,
12~3793
-- 4
24133-613D
and hydrated alumina having an average particle size less than 1~.
Preferably, said compositions also contain an impact modifier in
an amount sufficient to form a synergistic combination of impact
modifier with said hydrated alumina which substantially enhances
the impact strength thereof.
Also provided in accordance with the invention of the
parent application is a method for improving the weatherability
of filled polymeric vinyl halide material which comprises
incorporating in a polymeric vinyl halide material containing a
reinforcing filler, a hydrated alumina having an average particle
size less than about 1~.
There is also provided a composition which is suitable
for improving the impact resistance of polymeric vinyl halide
material which comprises an impact modifier which is a synthetic
high molecular weight polymeric rubbery material and hydrated
alumina having an average particle size of less than about 1~ in
the relative proportions of said impact modifier and hydrated
alumina that is sufficient to form a synergistic combination.
DETAILED DESCRIPTION OF THE INVENTION
Very fine particle size (less than about 1~ avg) hydrated
alumina compounded into impact modified rigid PVC formulations
gives compositions that surprisingly and unexpectedly exhibit a
significant synergistic increase in impact strength. The effect
has been demonstrated with a wide variety of impact modifiers
generally used in rigid PVC applications.
Torque rheometer and extrusion tests on rigid PVC formu-
lations containing such very fine particle size
i263793
hydrated alumina show that motor amperage and torques
decrease as hydrated alumina concentration increases.
Concurrently, an increase in dynamic heat stability was
observed.
Another benefit derived from the use of the very fine
particle size hydrated alumina in exterior PVC formulations
is improved weatherability with the potential for reducing
the amount of titanium dioxide or other fillers that are
conventionally used for particular applications.
10 Formulations compounded with various levels of the very fine
particle size hydrated alumina in accordance with the
invention outperformed those with titanium dioxide alone
when exposed to both outdoor and accelerated weathering
environments. In addition, formulations using reduced
15 levels of titanium dioxide in conjunction with said hydrated
alumina weathered as well as compounds using higher levels
of titanium dioxide alone.
As used herein, very fine particle size hydrated
alumina means hydrated alumina having an average particle
20 size of less than about l,u and preferably about 0.5~ (0.4 to
0.6~) or less. Generally, if the average particle size of
the hydrated alumina is greater than the above limit there
will be a deleterious effect on the Izod impact strength of
the material.
It is preferred that the particle size distribution of
the hydrated alumina be such that there is no substantial
percentage of particles which have a particle size greater
than about 1~.
The term "Impact Strength" means the Izod Impact
30 Strength as determined in accordance with the procedures of
ASTM D-256. Generally, this test is conducted by preparing
1263~93
--6--
samples measuring 2-1/2 x 1/2 x 1/~ or 1/4 inch in
dimension, notching the speciments as specified, and
impacting the specimens vertically supported in the
cantilever beam impact test with a pendulum hammer. The
5 energy absorbed in the width of the sample is transmitted to
a range scale which registers the force in pounds from which
is calculated the impact strength in foot pounds/inch of
notch.
The term "polymeric vinyl halide" means homopolymers
lO and copolymers derived from a vinyl halide as well as
polymer blends containing said homopolymer or copolymer as a
component. The homopolymers, copolymers and polymer blends
containing a vinyl halide useful in the practice of this
invention include for example, (1) polyvinyl chloride,
15 polyvinylidene chloride, polyvinyl bromide, polyvinyl
fluoride and polyvinylidene fluoride, (2) copolymers of
vinyl chloride with one or more copolymerizable
ethylenically unsaturated monomers such as vinylidene
chloride, vinyl acetate, vinyl butyrate, vinyl benzoate,
20 diethyl fumarate, diethyl maleate, other alkyl fumarates and
maleates, vinyl propionate, acrylic acid, methyl acrylate,
2-ethylhexyl acrylate, butyl acrylate, ethyl acrylate and
other alkyl acrylates, methacrylic acid, methyl
methacrylate, ethyl methacrylate, butyl methacrylate,
25 hydroxyethyl methacrylate and other alkyl methacrylates,
methyl alpha chloroacrylate, styrene, vinyl ethers such as
vinyl ethyl ether, vinyl chloroethyl ether and vinyl phenyl
ether, vinyl ketones such as vinyl methyl ketone and vinyl
phenyl ketone, l-fluoro, -l-chloroethylene, acrylonitrile,
30 chloroacrylonitrile, allylidene diacetate, chloroallylidene
diacetate, olefins such as ethylene and propylene, and t3)
- ~63793
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polymer blends such as blends of polyvinyl chloride and
polyethy]ene, polyvinyl chloride and polymethyl
methacrylate, polyviny] chloride and polybutvl chloride and
acrylonitrile-butadiene-styrene terpolymers and ternary
5 mixtures such as those containing polyvinyl chloride,
polyethylene methacrylate.
Typical vinyl halide copolymers useable in this
invention include vinyl chloride-vinyl acetate, vinyl
chloride-vinylidene chloride, vinyl chloride-diethyl-
10 fumarate, vinyl chloride-trichloroethylene and vinyl
chloride-2-ethylhexyl acrylate~ The polymer blends useable
in the practice of this invention comprise physical blends
of at least two or more distinct polymeric species and
typically contain from 25 to 9S weight percent of vinyl
15 halide homopolymer or vinyl halide copolymer. The vinyl
halide copolymexs useable in the practice of this invention
typically contain from about 25 to about 95 mole percent
vinyl halide units.
In preferred embodiments of the present composition,
20 the polymer is a homopolymer or copolymer of vinyl chloride.
This preference is based on the lower cost and commercial
availability of vinyl chloride relative to other vinyl
halides.
While the very fine particle size hydrated alumina
25 herein described may be used as a filler material in both
rigid and flexible polymeric vinyl halide formulations, the
surprisingly superior impact strength that can be achieved
is of particular commercial significance in rigid
formulations (those having less than 10~ plasticizer).
The parameters surroundins and the effect of the use of
a very fine particle size hydrated alumina in accordance
1~3793
with the practice of the invention will now be discussed seriatum,
with reference to the accompanying drawings, in which:
Figure 1 is a graphical illustration of the effect of
hydrated alumina concentration on the Izod impact strength of a
polymeric vinyl halide formulation;
Figure 2 is a graphical illustration of the effect of
hydrated alumina on extrusion, measured as head pressure, and
torque, m~asured as motor amperage, for a second polymeric vinyl
halide formulation; and
Figure 3 is a graphical illustration of the effect of
hydrated alumina and calcium carbonate on weathering of a rigid
PVC formulation.
A Impact Synergism
When calcium carbonate fillers with an average particle
size over 1.0~ are used in rigid PVC formulations, they generally
have an adverse effect on impact strength. When the average
particle size is less than 1.0~, there is no loss in impact strength
and, occasionally a slight improvement in impact strength will
occur. In formulations containing bGth impact modifiers and
calcium carbonate fillers, there are only slight improvements in
impact strength over that obtained with the impact modifier itself.
In non-impact modifier containing PVC formulations the
very fine-particle size hydrated alumina used in accordance with
this invention also gives small increases in impact strength.
However, in PVC formulations containing impact modifiers, hydrated
alumina having a very fine particle size (less than about 1~) as
herein described behaves dramatically different than calcium
-- 8 --
~2637~3
carbonate and acts synergistically with the impact modifier to
give a significant and unexpected increase in impact strength.
These results are shown in Table 1.
The surprising and unexpected increase in impact
strength that is achieved is independent of the type of impact
modifier used in the formulation. Impact modifiers generally
are rubbery materials which are either partially or completely
incompatible with the polymeric vinyl halide and are present
as a separate discrete phase. This is in contra5t to
plasticizers which are completely compatible with the
polymeric vinyl halide. Further, impact modifiers
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~1263793
-9- 24133-613D
improve impact strength without significantly reducing the
heat distortion temperature or impairing other desirable
mechanical and physical properties. Representative impact
modifiers included but are not limited to chlorinated polyethylene,
modified acrylic, all-acrylic, ABS and MBS modifiers. It is
believed that any conventional impact modifier can be used in the
formulations and that the very fine particle size hydrated
alumina will continue to show these synergistic effects. For
example, the addition of 6 parts per hundred parts resin of very
fine particle size hydrated alumina to rigid PVC formulations
containing 5 phr of a conventional impact modifier gave increases
in Izod impact strength from almost twice to over ten times the
impact strength obtained without the addition of hydrated alumina.
The data in Table 2 demonstrated that increases in Izod impact
from 5-20 ft.-lbs./in. notch can be obtained.
Hydrated Alumina ParticlP Size
While the use of small particle size hydrated alumina
(average size of 1~) is not detrimental to the impact strength of
PVC formulations and the use of larger particle size hydrated
alumina will reduce the impact strength of the PVC composition,
the very substantial increase in impact strength that is achieved
with a synergistic combination of a conventional impact modifier
and the very fine particle size (less than 1~) hydrated alumina
as herein described is totally unexpected and surprising.
Table 3 shows that impact synergism is specific to
hydrated alumina with an average particle size below about
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1~. Tests with an average particle size of 1~ show no
effect on impact while larger particle size materials are
detrimental to impact strength.
C. Hydrated Alumina Concentration
We have determined that maximum increase in impact
strength appears to occur at a ratio of very fine particle
size hydrated alumina to impact modifier of about 2-4:1, but
significant increases in impact strength are obtained even
at a 1:1 ratio and some useful effect is noticed as low as a
1:2 ratio. Even lower ratios may be used with some effect
but generally commercially significant results necessitate
at least the 1:2 ratio.
For example, with a formulation containing 3 phr
modified acrylic modifier, maximum impact was obtained at at
a ratio of 2:1 hydrated alumina to impact modifier. When
the concentration of hydrated alumina was increased to an
8:1 ratio of hydrated alumina to impact modifier, impact
strength equivalent to 3 phr impact modifier without
hydrated alumina was obtained (Figure 1).
Impact modifiers are generally utliized in the range of
about 1 phr to about 15 phr, and preferably in the range of
about 2 phr to about lC phr. The particular level will
depend on the end use of the material. For example,
injection molded PVC generally has an impact modifier level
of about 2-3 phr while rigid PVC used for building siding
has a usual level of about 4-8 phr. The use of verv small
particle size hydrated alumina in accordance with this
invention will allow the use of somewhat lower levels of
impact modifier. Inasmuch as high levels of impact modifier
tend to reduce tensile strength and heat distortion
i263~9~
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temperature, the reduced level of impact modifier can
provide polymeric vinyl halide materials which exhibit
somewhat superior physical properties.
Optimum concentration of impact modifier and hvdrated
alumina will depend upon the formulation and desired
performance characteristics of the compound. For example,
if an Izod impact of 2.0 is sufficient for an outdoor
weathering compound, then the data shown in Figure 1
illustrates that a formulation with 3 phr impact modifier
can contain as much as 24 phr hydrated alumina and still
maintain the same impact strength while taking ad~antage of
the surprising improvement in weathering and processing
characteristics also described herein and shown in Tables 6
and 7 and Figure 2. If improved impact is also desired, the
lS hydrated alumina concentration can be reduced somewhat to
obtain the desired impact properties while still obtaining
advantageous weathering.
While as described above, the ratio of hydrated alumina
to impact modifier can be as high as 8:1, it is preferred
that the concentration of hydrated alumina be no higher than
about 50 phr. If the level is greater than 50 phr, the
processing characteristics may deteriorate and it may be
difficult to distribute the hydrated alumina uniformly
throughout the polymeric material.
D. Processibility
The addition of very fine particle size hydrated
alumina to rigid PVC formulations as herein described
results in improved processing characteristics as evidenced
by reduced torques, stock temperatures and pressures, as
well as increased dynamic processing stability.
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A standard siding formulation containing, for example,
10 phr of said very fine particle size hydrated alumina,
maintained an equilibrium torque of 1525 meter-grams and a
stock temperature of 206C compared to 1650 meter-grams and
208C for the same formulation without hydrated alumina. In
the same torque rheometer study, the compound with 10 phr
hydrated alumina showed a 13~ increase in heat stability
with a stability time of 22.2 minutes compared to 19.6
minutes for the control. The saMe compound with 6 phr of
said hydrated alumina gave a 9% increase in heat stability
over the control (Table 4).
In addition to the torque rheometer studies, the same
compounds were processed under controlled conditions on a
Kraus-Maffei 25 mm conical twin screw laboratory extruder
equipped with a 2-1/2", 40 mil strip die. The use of very
fine particle size hydrated alumina resulted in reduced
tor~ues tlower motor amperage) and pressures. The data is
shown in Figure 2.
A common problem among weatherable rigid PVC processors
is screw and barrel wear caused by the abrasiveness of
titanium dioxide (Moh hardness about 6.5). Unlike alumina,
which is very hard (Moh hardness about 9), hydrated alumina
is relatively soft and similar to calcium carbonate with a
Moh hardness of about 3. The potential for reduced ti,tanium
25 dioxide levels when formulating with the very fine particle
size hydrated alumina could lead to reduced barrel and screw
wear.
E. Weatherability
Another surprising and unexpected benefit derived from
the use of the very fine particle size hydrated alumina as
.
lZ63793
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herein described in rigid PVC formulations is improved
weatherability with the potential for reducing Tio2
levels. For example, a standard siding formulation was
compounded with various levels of very fine particle size
hydrated alumina and extruded on the KM-25 laboratory
extruder. Accelerated light stability testing of extruded
samples in a Fluorescent Sunlamp/Black Light (FSBL) light
source showed that the addition of hydrated alumina improved
light stability (Table 5).
Another series was similarly extruded and ~ested in a
QUV machine. It also showed that addition of very small
particle size hydrated alumina improved light stability. In
this series, a formulation containing 10 phr TiO2 and 6
phr of such hydrated alumina appeared to be at least
equivalent in light stability to the control formulation
containing 12 phr Tio2 and no hydrated alumina (Table 6~.
Long term outdoor weathering tests have been conducted
with hydrated alumina formulations for 12 months. White
compound extruded strips were weathered 45 south in Arizona
and green compound extruded strips were weathered 45 south
in Florida. The results as shown in Tables 7 and 8 show
this improvement.
Arizona weathering tests conducted on rigid PVC
formulations containing very small particle size hydrated
alumina and calcium carbonate show that the compound
containing calcium carbonate was more susceptible to
yellowing and subsequent chalking than either the control or
the formulation containing hydrated alumina. This
characteristic of calcium carbonate is the reason this
filler is not widely used in exterior compounds, especially
iZ~;3~3
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colored formulations where chalking is especially detrimental
(Figure 3).
Variable height impact tests (VHIT) were run on the
green extruded strips prepared for Florida weathering tests.
Impact results on the extruded samples containing hydrated
alumina in accordance with the invention were equivalent to the
control (Table 8).
In addition to the very fine particle size hydrated
alumina and impact modifiers herein described, the polymeric
vinyl halide compositions may contain the usual compounding
ingredients such as stabilizers and fillers and optional additives
such as pigments, lubricants, dyes, ultraviolet light absorbing
agents, plasticizers and the like.
Generally, the very fine particle size hydrated alum-~
ina may be introduced into the polymeric vinyl halide formulat-
ion in any conventional manner, such as by preblending the
selected hydrated alumina and impact modifier before blending
with the polymeric resin, or alternatively, the components are
blended individually in the resin. It is of course necessary
that it be dispersed substantially uniformly throughout the
mixture. In extruded formulations incorporation of hydrated
alumina tends to reduce back pressure, so one should be careful
that sufficient shear exists for thorough dispersion.
Conventional processing temperatures and conditions may
be utilized so long as the processing temperature remains below
about 230 C. If the processing temperature is higher than that
value, there may be some decomposition of the hydrated alumina
due to loss of water.
~;~93 --
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EXAMPLE 1
Izod impact specimens were prepared using 35-40 mil
sheet, milled at 325F for five minutes after banding. The
milled sheet was then cut into four 6" x 6" sheets and
plied, alternating the oriented sheets. The samples were
compression molded into 1/8" plaques at 375F for ten
minutes at 3000 PSI. Izod impact strength was determined
according to ASTM D-256. Physical properties were
determined according to the procedures described in ASTM
D-1784.
Torque rheometer dynamic processing stability was
obtained using a Brabender*lasti-Corder (C. W. Brabender,
Hackensack, N. J.) electrically heated torque rheometer
equipped with a No. 6 bowl according to the conditions
1~ identified in the tables.
Accelerated and outdoor weathering and variable height
impact test (VHIT) were all determined on e~truded strips
obtained from compounds blended in a high intensity mixer
and extruded under the same conditions on a KM-25 la~oratory
extruder equipped with a 2-1/2", 40 mil strip die.
Extrusion conditions were Zones ~ 2 and #3, 320F, 295F,
325F, respectively, and 380F on the die at 20 rpm screw
speed.
Variable height impact tests were carried out according
to procedures described in ASTM D-3679.
Outdoor and accelerated weathering tests were carried
out as follows:
Outdoor Weathering - All samples were exposed 45 south
with backing.
* Trade Mark
~2~793
Fluorescent Sunlamp/Black Light (FSBL) - Samples were
exposed with a repeating cycle of 100 hours U.V.
exposure followed by 68 hours dark time.
Q W - Accelerated Weathering Test - Samples were
exposed with a repeating cycle of 2 hours U.V. at 50C
followed by 4 hours condensate at 50C using equipment
conforming to ASTM G-53 manufactured by the Q-Panel
Co., Cleveland, Ohio.
10 The following formulation materials were produced.
Formulation ''A''
PVC (K-65~ 100.0
TiO2 (rutile) 2.0
Calcium Stearate 0.8
Paraffin Wax, 165F 1.2
Processing Aid 1.0
Butyltin Mercaptide Stabilizer 1.5
Formulation "B"
PVC (K~65~ 100~0
TiO2 (rutile) 12.0
Modified Acrylic Modifier 5.0
Processing Aid 0.3
Calcium Stearate 2.0
Paraffin Wax, 165F 1.0
Butyltin Mercaptide Stabilizer 1.5
~Z~3~93
Formulat_on "C"
PVC (K=65) 100.0
TiO2 (rutile) 6.0
Modified Acrylic Modifier 5.0
Processing Aid 1~0
Calcium Stearate 2.0
Paraffin Wax, 165F 1.0
Butyltin Mercaptide Stabilizer 1.5
Formulation "A: was used for the Izod impact studies,
the results of which are summarized in Tables 1, 2 and 3;
and Formulation "B" was used for torque rheometer stability
studies, extxusion, variable height impact testing and
weathering studies, the results of which are summarized in
Tables 4, 5, 6, 7 and 8. Formulation "C" was used for a
weathering study in which hydrated alumina was compared to
calcium carbonate, the results of which are shown in Figure
3. For green siding compound, a non-chalking grade of
titanium dioxide was substituted for the chalking grade of
titanium dioxide used in the white siding compound. Unless
otherwise noted, hydrated alumina referred to in the tables
was prepared by a precipitation process and had an average
particle size of 0.5,u.
~Z~;3793
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The following tables illustrate the effects ofhydrated alumina on various properties of rigid PVC
materials.
TABLE 1
SYNERGISM OF HYDRATED ALUMINA & I~MPACT MODIFIER
Formulation '_"
Variable ~ 1 2 3 4 5 6 7 8 9
Modified Acrylic - 5 - 5 3 - 3 - 3
Hydrated Alumina - - 12 12 - 6 6 - -
Calcium Carbonate(l) - - - - - - - B 6
Izod Impact 0.8 14.3 1.8 18.3 2.1 1.6 8.1 1.0 2.2
(ft.-lbs./in.-notch)
(1) Coated, average particle size 0.8u.
, .. . .. . . . . . . .. .. .. ... . . . .... . . . .. .
~2637~3
- 19 24133-~13
o o q~
~1. I , , I
I
ol o u~
I I , I
I o o t:n
a~ . I I I . I
~ O
col I I I I 0. 1 In
~H¢ u~~J
~ I O ~ ~
a
5: ~1 ~
H I o o a~ U :>1
a a u
3 ~
H ~1 ~ ~ V S~
O ~ rl O
~ ~ ~1 ~D ~ I I I I ~ ~ ~ a
i~l ~ ` ~
1 u~ m ,~ ~ x
I o I o ~~ ttt
~o ,t)
O V ~ H D V ~
14 a) ~ ~ !~
~ ~ ~ 3~
, h ~ O ~ ~ ~a ~1
~ ~,1 o o ,I m ~ m N 1~1 0 0 ~I m ~
:~ ~ X ~ ~æ ~ *
~37~33
-20-
TABLE 3
EFFECT OF PARTICLE SIZE AND FILLER TYPE
(Formulation "A")
phr
Variable 1 2 3 4 5 6
Modified
Acrylic 3.0 3.0 3.0 3.0 3.0 3.0
Hydrated
Alumina - 6.0 6.0 6,0 - -
Alumina - - - - 6.0- -
Hydrated
Silica ~ - 6.0
Average
Particle
Size, u. - 0.5 1.0 8.0 1.0 0.12
Izod Impact2.1 8.1 2.1 1.0 0.7 2.0
(ft.-lbs~/
in.-notch)
~2~;3793
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TABLE 4
EFFECT OF HYûRATED ALU~IINA
ON DYNA.UIC PROCESSING STABILITY(l)
Variable
Formulation A A B B B
TiO2 2.0 2.0 12.012.012.0
Modi~ied Acrylic 3.0 3.05.0 5.0 5.0
Hydrated Alumina - 6.0 - 6.0 10.0
Stability, ~in. 25.3 ?7.519.621.3 22.2
Equil.Torque,
m-g. 2250 2200 165018001525
(1) Torque Rheometer
Formulation "A: - 200C, 60g. charge 60 RPM
Formulation "B: - 200C, 65g, charge 75 RPM
,.. . .. . . . . . . . . .. .. . . .
~26~793
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TABLE 5
THE EFFECT OF HYDRATED ALUMI~A ON
FSBL. (1) ACCELERATED WEATHERING
Variables 1 2 3 4 5 6
Modified Acrylic 3 3 3 4 4 4
Hydrated Alumina - 4.0 6.0 - 4.0 6.0
Hours Yellowness Index
Initial 4.6 4.9 4.9 4.4 4.6 4.7
500 9.6 9.2 8.5 8.4 7.8 8.1
lOOO 16.1 14.5 13.7 14.0 12.8 12.6
1500 18.6 16.3 16.1 16.4 15.6 14.5
(1) Fluorescent Sunlamp/Black Light
TABLE 6
THE EFFECT OF HYDRATED ALUMINA ON
QUV ACCELERATED WEATHERIMG
(Formulation "B")
Hydrated Yellowness Inde~
TiO2,phr Alumina, phr Initial 2 Wks. 4 Wks. 10 Wks.
12 - 4.4 6.310.5 13.2
12 6 3.2 5.3 8.3 11.2
12 10 3.2 5.7 8.5 10.7
6 3.2 5.6 8.8 11.8
,. . . . . . .. .. .. . . . . . . . . . .. ... . . . . . . .
~2637~3
-23-
TABLE 7
THE EFFECT OF HYDRATED ALUMINA
ON WEATHERI~G ~1)
(Formulation "B")
Variables 1 _ 2 3 _
TiO2 12 12 12
Modi~ied Acrylic 5 5 5
Hydrated Alumina - 3.0 6.0
Months _ Yellowness Inde~
0 3.0 3.0 3.1
3 9.4 804 6~4
6 10.0 9.1 6.3
9 11.6 9.9 6.7
12 14.2 13.6 9.7
(1) Arizona
, . , . . . . . , . , , . _ .. . . . ~ . . .... . . . .
~63~7g3
-24-
TABLE 8
THE EFFECT OF HYDRATED ALUMINA ON
WEATHEP.ING (1)(2~
Variables 1 2 _ 3 4
TiO2 12 12 12 12
~odi~ied Acrylic 5 5 3 3
Hydrated Alumina - 6 - 6
VHIT, In.-Lbs/
Mil, 23C 3.4 3~4 3.6 3.5
Months _ E(3)
3 .3 .3 .4 .5
6 .6 .2 .5 .2
9 .7 .2 .6 .3
12 1.0 .7 .9 .5
(1) Florida
(2) Formulation "B", non-chalking TiO2, 1.5 phr chrome
o~ide
(3) ASTM D-2244
. . .... . . ... .... .. . . . . . .. . . .. . . .
~263793
-25-
EXAMPLE 2
A series of polyvinyl chloride formulations were
prepared using the proportion of ingredients listed in Table
9 to evaluate the effect of hydrated alumina on
weatherability of formulations prepared with or without
impact modifiers and/or plasticizers. Accelerated
weathering tests (FSBL and QUV) described in Example l were
used to evaluate each of the formulations and the results
are also summarized in Table 9.
Each of the formulations of this example were milled
for 5 minutes at 350F after bonding and test samples were
compression molded at 350F for 5 minutes into 125 mil
plaques. Yellowness index was obtained on a ~CBETH 1500
colormeter.
It can be seen from the results reported in Table 9
that each of the formulations containing very fine particle
size hydrated alumina (0.5u avg) exhibited improved
weatherability over those formulations which did not contain
said hydrated alumina. This improvement in weatherabili~y
can be seen for formulations which were prepared with or
without an impact modifier or plasticizer, and with
formulations containing both an impact modifier and
plasticizer. While the results show that the impact
modifier and plasticizer used in the formulations of this
example result in improved weatherability, the use of
hydrated alumina having an average particle size of 0.5u
further enhanced the weatherability of the formulation.
~(~ ~63793
I ~) 5 c~ 5 -- ~ C I`
C~;t O C`t ~ ~ U~ Ci _
I C C ^ C ~ O ' ~ r~ t~ 0 ~5 ~
.J
o o cq o c u~ o o c c lt~
O ~ t O `t ~ O ~
o c c~ o ~ n o 5 C~ ~' - X ~ ~-
G~ - ~t C C; ~ ~ c: C ^ O ~`t ~t ~ O ''
O O ~q O C ~ O O O e~ C~t
t g C`t 5 c~t ~ C\t t~ ~ o s~
r~
~ c ~ o o ~ o o r~ 0 U: C`;t
:- _ ~t O C~t ~ '' ~ t I -- C G~
C O :q 5 0 u~t C O O ~ t` ~ C~
t~t I C C t C ~t ~ t `t C ~ O
~l
s~l o ~ ^ -- c o ~`l ~ c ;- ; o c - o
n ,~ O c~t c ~-;t ,~ o ~n ~ o ~ Ii '$eO c~
~t ¦ _ '~ O O 1~' 0 0 0 L~ O X -- I ~t y ~
_ ~ O ~`i O ` i ~ ~t t 3 ~ S t` 5 ~-- t? Cr~t ~k
j ~1 5 I~ ~ C U~
C c~t C ~i r~ ! C~
O -~
o o cq o o n ~ o
C;l ~ t ~~ t~ o - c ^i r, c --.
~ rt
O O ~ O o ~ I I I ~ O ~ ~ ~ ct ~ ~
,, O ~i O ~, ,, ~ ~ ~ , ai ', ,, '' ,-
,~
t_ ~ ~
~ ~ 0 ~ ? ~? '~? ` ~ '`
C ~ . X ;~ ~ C
~:~3~
. ~ al
793
-27-
EXAMPLE 3
A series of polyvinyl chloride formulations were
prepared using the proportion of ingredients listed in Table
10 to evaluate the effect of hydrated alumina on
weatherability. Accelerated weathering tests (FSBL and Q W)
described in Example 1 were used and the results obtained
are summarized in Table 11.
Each of the formulations of this example were milled
for 5 minutes at 350F after bonding. Formulations 1 to 5
were prepared by individually adding each of the ingredients
and formulation 6 was prepared by preblending the impact
modifier, stabilizer, processing aid, Tio2 and hydrated
alumina were prepared by individually adding each of the
ingredients and formulation 6 was prepared by preblending
the impact modifier, stabilizer, processing aid, TiO2 and
hydrated alumina.
It can be seen from the results shown in Table 11 that
the addition of a hydrated alumina having an average
particle size of 0.5u and O.9u to polyvinyl chloride
formulations enhanced the weathering characteristics thereof
as compared to a formulation which did not contain the
hydrated alumina filler. It can also be seen from the
results that hydrated alumina having an average particle
size of 0.5u enhanced the weatherability of PVC formulations
which contained an impact modifier and these advantageous
results were obtained with the compounding ingredients being
added individually or as a preblended mixture.
~' .
~2G~793
--28--
0
~a
o ~ o o o o o ~
..... I ~
O O ~1 ~ C`~ C`J ~ ~ u~ C~
o o
,~ o
q~ ~
,~, o o
O1~ 0 00 011~ ~ N
. . . I. .I. ~1 rl
u~ O O ~
O
~ ~.,
,_I O U~ O O O O O U~
S~ I g O ~ 1 , C) g ,~
N c~
i: ~ h h
O E~ ~
O O OI U~
O 11~ 0 0 0 0
C'J O O ~ N
'~ S
Z S ~; bD S.
O C.) ~( 5 0 ~ U~
o u~ o oo u~ E a~
--~¦o o ~ h ~,
a) o ~ . ~ v
+~ V I h ~ q~
O C .~d ~ ~ y E
~ Ch i-- '~3 ~ m ~ C~
C ~ ~ct ~ E ¢ ~,1O C c~ ~'
~ h ~ O h r
S ~ N
co ~ v
O ~ ~d CJ V h O h O .i:l
~) O h ~ O ,1 ~ ~ ~1 ~ a~
::~ h ~ ~ p ~ ~ ~ "~ -
-
- ~Z637~3
-29-
TABLE 11
Q W ACCELERATED WEATHERING
Yellowness Index
Formulations
l 2 3 4 5 6
Initial Y.I. 7.6 7.8 8.4 9.2 8.2 11.5
~Y.I. 168 hrs. 5.4 3.8 3.8 2.0 4.0 3.1
336 hrs. 16.0 8.9 8.4 5.1 9.4 5.9
420 hrs. 19.0 10.9 10.8 5.8 10.9 6.1
FSBL ACCFLERATED WEATHERING
Yellow~ess Index
Formulations
1 2 3 4 5 6
Initial Y.I. 7.6 7.8 8.4 9.2 8.2 11.5
QY.I. 168 hrs. 2.3 1.4 1.0 1.0 1.7 1.5
336 h~s. 4.1 1.8 2.3 l.0 3.0 1.4
