U.S. patent application number 16/396370 was filed with the patent office on 2021-08-26 for elastomer composite including algae biomass filler.
This patent application is currently assigned to ALGIX, LLC. The applicant listed for this patent is ALGIX, LLC. Invention is credited to Mark Ashton Zeller.
Application Number | 20210261761 16/396370 |
Document ID | / |
Family ID | 1000005764787 |
Filed Date | 2021-08-26 |
United States Patent
Application |
20210261761 |
Kind Code |
A9 |
Zeller; Mark Ashton |
August 26, 2021 |
ELASTOMER COMPOSITE INCLUDING ALGAE BIOMASS FILLER
Abstract
An algae-elastomer composite including an elastomer matrix;
algae; and a mixing additive sufficient to achieve a desired
property. The algae can be present in a milled condition having a
particle size value of between about 10 and 120 microns. The algae
is mixed with the elastomer matrix in a dry condition having a
moisture content of below about 10%. A method of preparing the
algae-based elastomer composite is provided that includes the steps
of: premixing an elastomer matrix; adding an algae filler; adding a
mixing additive that includes a plasticizer; forming an
elastomer-algae blend by blending the algae and elastomer to a
temperature sufficient to be further mixed, wherein the temperature
is about 10.degree. C. higher than the temperature sufficient for
the elastomer alone; adding and mixing a curing or vulcanizing
agent for the elastomer dispersing the elastomer-algae blend; and
heating and curing the elastomer-algae blend into a final form.
Inventors: |
Zeller; Mark Ashton;
(Meridian, MS) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ALGIX, LLC |
Meridian |
MS |
US |
|
|
Assignee: |
ALGIX, LLC
Meridian
MS
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20190330453 A1 |
October 31, 2019 |
|
|
Family ID: |
1000005764787 |
Appl. No.: |
16/396370 |
Filed: |
April 26, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62663893 |
Apr 27, 2018 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08L 7/00 20130101; C08L
15/005 20130101; B29D 35/0054 20130101; C08L 23/16 20130101; C08L
9/02 20130101; C12N 1/12 20130101; B29D 35/122 20130101; B29K
2009/06 20130101; C08L 11/00 20130101; C08L 9/06 20130101; B29C
70/58 20130101; B29D 35/065 20130101; C08L 23/286 20130101; C08L
19/00 20130101 |
International
Class: |
C08L 9/06 20060101
C08L009/06; B29C 70/58 20060101 B29C070/58; B29D 35/00 20060101
B29D035/00; B29D 35/06 20060101 B29D035/06; B29D 35/12 20060101
B29D035/12; C12N 1/12 20060101 C12N001/12; C08L 9/02 20060101
C08L009/02; C08L 11/00 20060101 C08L011/00; C08L 19/00 20060101
C08L019/00; C08L 23/16 20060101 C08L023/16; C08L 23/28 20060101
C08L023/28; C08L 15/00 20060101 C08L015/00; C08L 7/00 20060101
C08L007/00 |
Claims
1. A algae-elastomer composite comprising: (a) an elastomer matrix;
(b) a biomass reinforcement distributed through the elastomer
matrix, wherein the biomass comprises algae; and (c) a mixing
additive sufficient to achieve a desired property.
2. The composite of claim 1, wherein the algae is present in a
milled condition having a mean particle size value of up to 120
microns.
3. The composite of claim 1, wherein the algae is mixed with the
elastomer matrix in a dry condition having a moisture content of
below about 20%.
4. The composite of claim 3, wherein the algae is mixed with the
elastomer matrix in a dry condition having a moisture content of
below about 3%.
5. The composite of claim 1, wherein the elastomer matrix is
selected from the group consisting of Natural Rubber (NR),
Butadiene Rubber (BR), Acrylonitrile Butadiene Rubber (NBR),
Styrene Butadiene Rubber (SBR), Hydrogenated Acrylonitrile
Butadiene Rubber (HNBR), Ethylene Propylene Diene Rubber (EPDM),
Chloroprene Rubber (CR), Chlorinated Polyethylene Rubber (CM),
Silicone Rubber (Q), and combinations thereof.
6. The composite of claim 1, wherein the algae is present in an
amount between about 1% to 75% by weight of composite.
7. The composite of claim 1, wherein the algae is selected from the
group of algae species consisting of Haptophyta, Cyanophyta,
Chlorophyta, Ochrophyta, Rhodophyta, Phaeophyta and combinations
thereof.
8. The composite of claim 1, wherein the algae biomass includes
protein, ash, carbohydrate, and lipids by weight at a composition
of protein from about 1% to 60%, ash from about 1% to 90%,
carbohydrate from about 1% to 50%, and lipid from about 1% to
30%.
9. The composite of claim 1, wherein the mixing additive comprises
at least one of plasticizer or performance enhancing additive
operable to deliver a desired property of the composite
material.
10. The composite of claim 1, wherein the elastomer is present in a
premixed condition resulting in a plasticized state.
11. The composite of claim 1, further comprising an additive
selected from the group consisting of an elastomer compound having
polar functionalization, a thermoplastic compound having polar
functionalization, a compatibilizer, a coupling agent, and
combinations thereof.
12. The composite of claim 11, wherein the elastomer compound
having polar functionalization or the thermoplastic compound having
polar functionalization comprises a functionalizing agent selected
from the group consisting of a carboxylate, styrene, methyl
methacrylate, acrylonitrile, glycidyl methacrylate, maleic
anhydride, epoxide, and combinations thereof.
13. The composite of claim 11, wherein the additive is a coupling
agent having at least one member selected from the group consisting
of isocyanate, peroxide, glyoxal coupling agents (XNBR) and
combinations thereof.
14. The composite of claim 11, wherein the additive is present in a
premixed condition with the elastomer matrix.
15. A shoe component comprising the algae-elastomer composite of
claim 1, wherein the shoe component is selected from the group
consisting of an outsole, midsole, insole and combinations
thereof.
16. A method of preparing an algae-based elastomer composite, the
method comprising: (a) premixing an elastomer matrix in a mixer for
a period of time sufficient to plasticize the elastomer into a
suitable condition for mixing; (b) adding an algae filler into the
mixer, wherein the algae filler is provided as particles; (c)
blending the algae and elastomer to form an elastomer-algae blend,
wherein the blend is heated to a temperature sufficient to be
further mixed and wherein the temperature is about 10.degree. C.
higher than the temperature sufficient for the elastomer alone; (d)
adding and mixing a curing or vulcanizing agent for the elastomer,
wherein the amount of curing or vulcanizing agents are provided in
an amount of about 10% to 500% more than sufficient to provide to
cure or vulcanize an elastomer absent the algae; (e) dispersing the
elastomer-algae blend; and (f) heating and curing the
elastomer-algae blend into a final form.
17. The method of claim 16, further comprising the step of
incorporating at least one additive selected from the group
consisting of an elastomer compound having polar functionalization,
a thermoplastic compound having polar functionalization, a
compatibilizer, a coupling agent, and combinations thereof, to the
premixing step (a) to enhance compatibility of the algae with the
elastomer.
18. The method of claim 16, wherein the heating and curing step (f)
includes extruding through an extruder to heat and mix the blend
followed by passing through a heating tunnel to be cured and foamed
into an elastomer-algae blend foam sheet.
19. The method of claim 16, wherein the heating and curing step (f)
forms flat sheets and includes the step of applying the flat sheets
or pre-cut forms to a mold to press the blend into a desired form
prior to the heating and curing step.
20. The method of claim 19, wherein the desired form is a shoe
component selected from the group consisting of as an outsole,
midsole, insole or the like.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to and the benefit of U.S.
Provisional Patent Application No. 62/663,893, titled "ELASTOMER
COMPOSITE INCLUDING ALGAE BIOMASS FILLER," and filed on Apr. 27,
2018, the disclosure of which is incorporated herein by reference
in its entirety for all purposes.
TECHNICAL FIELD
[0002] The present disclosure relates generally to the field of
elastomers and elastomer composite production using biomass.
DESCRIPTION OF RELATED ART
[0003] Rubber and elastomer composites are often desired for
consumer goods, particularly for footwear, anti-fatigue mats,
gasketing, insulation, sporting goods, automotive parts, and other
related industries. An elastomer composite includes a filler
material that may modify the elastomer to result in desired
mechanical, thermal and other physical properties such as hardness,
durability, strength, resilience, temperature stability, and the
like. Moreover, there is an environmental incentive to identify
reusable filler components to reduce the negative impact of using
fossil fuels to manufacture products and in the case of algae to
improve the trophic state of waters from which the algae is removed
from with wide ranging ecological benefits.
[0004] U.S. Pat. No. 9,574,066 to Du et al. discloses a rubber
composition comprised of at least one conjugated diene-based
elastomer containing triglyceride based algae oil and to a tire
with a component thereof.
[0005] Despite other attempts to solve the problems associated with
a forming elastomer composites, none of these teach or suggest a
material and/or method having the benefits and features of the
present disclosure.
SUMMARY
[0006] The present disclosure provides for a biomass-elastomer
composite including an elastomer matrix and a biomass reinforcement
distributed through the elastomer matrix, wherein the biomass
includes algae. The algae biomass may further include any additives
sufficient to achieve a desired mixing and/or property. The biomass
can further be provided directly as dry algae in particle form or
in a masterbatch combined with a thermoplastic. The composite can
be a solid composite or a foam composite.
[0007] The present disclosure provides for an algae-elastomer
composite including: (a) an elastomer matrix; (b) a biomass
reinforcement distributed through the elastomer matrix, wherein the
biomass includes algae; and (c) a mixing additive sufficient to
achieve a desired property. In an example, the algae is present in
a milled condition having a mean particle size value of between up
to about 120 microns. The algae can mixed with the elastomer matrix
in a dry condition having a moisture content of below about 20%. In
another example, the algae is mixed with the elastomer matrix in a
dry condition having a moisture content of below about 3%. The
elastomer matrix can be selected from the group consisting of
Natural Rubber (NR), Butadiene Rubber (BR), Acrylonitrile Butadiene
Rubber (NBR), Styrene Butadiene Rubber (SBR), Hydrogenated
Acrylonitrile Butadiene Rubber (HNBR), Ethylene Propylene Diene
Rubber (EPDM), Chloroprene Rubber (CR), Chlorinated Polyethylene
Rubber (CM), Silicone Rubber (Q), and combinations thereof. The
algae can be present in an amount of between about 1% to 75% by
weight of composite. In yet a further example, the algae is
selected from the group of algae species consisting of Haptophyta,
Cyanophyta, Chlorophyta, Ochrophyta, Rhodophyta, Phaeophyta and
combinations thereof.
[0008] Algae biomass typically includes protein, ash, carbohydrate,
and lipids. In an example, the algae biomass includes a composition
of protein from about 1% to 60%, ash from about 1% to 90%,
carbohydrate from about 1% to 50%, and lipid from about 1% to 30%.
The mixing additive can include plasticizers and performance
enhancing additives operable to deliver the desired properties of
the composite material. In yet another example, the elastomer is
present in a premixed condition resulting in a plasticized
state.
[0009] The composite of the present disclosure can further include
an additive selected from the group consisting of an elastomer
compound having polar functionalization, a thermoplastic compound
having polar functionalization, a compatibilizer, a coupling agent,
and combinations thereof. The elastomer compound having polar
functionalization or the thermoplastic compound having polar
functionalization can further include a functionalizing agent
selected from the group consisting of a carboxylate, styrene,
methyl methacrylate, acrylonitrile, glycidyl methacrylate, maleic
anhydride, epoxide, and combinations thereof. In yet another
example, the additive is a coupling agent having at least one
member selected from the group consisting of isocyanate, peroxide,
glyoxal coupling agents (XNBR) and combinations thereof. In still
another example, the additive can be present in a premixed
condition with the elastomer matrix.
[0010] The present disclosure provides for a shoe component
including the algae-elastomer composite of and of the examples
previously disclosed, wherein the shoe component is selected from
the group consisting of an outsole, midsole, insole and
combinations thereof.
[0011] The present disclosure further provides for a method of
preparing an algae-based elastomer composite, the method including
the steps of: (a) premixing an elastomer matrix in a mixer for a
period of time sufficient to plasticize the elastomer into a
suitable condition for mixing; (b) adding an algae filler into the
mixer, wherein the algae filler is provided as particles; (c)
blending the algae and elastomer to form an elastomer-algae blend,
wherein the blend is heated to a temperature sufficient to be
further mixed and wherein the temperature is about 10.degree. C.
higher than the temperature sufficient for the elastomer alone; (d)
adding and mixing a curing or vulcanizing agent for the elastomer,
wherein the amount of curing or vulcanizing agents are provided in
an amount of about 10% to 500% more than sufficient to provide to
cure or vulcanize an elastomer absent the algae; (e) dispersing the
elastomer-algae blend; and (f) heating and curing the
elastomer-algae blend into a final form. The method can further
include the step of incorporating at least one additive selected
from the group consisting of an elastomer compound having polar
functionalization, a thermoplastic compound having polar
functionalization, a compatibilizer, a coupling agent, and
combinations thereof, to the premixing step (a) to enhance
compatibility of the algae with the elastomer. In another example,
the heating and curing step (f) includes extruding through an
extruder to heat and mix the blend followed by passing through a
heating tunnel to be cured and foamed into an elastomer-algae blend
foam sheet. In yet a further example, the heating and curing step
(f) forms flat sheets and includes the step of applying the flat
sheets or pre-cut forms to a mold to press the blend into a desired
form prior to the heating and curing step. In still yet another
example, the desired form is a shoe component selected from the
group consisting of as an outsole, midsole, insole or the like.
[0012] For purposes of summarizing the disclosure, certain aspects,
advantages, and novel features of the disclosure have been
described herein. It is to be understood that not necessarily all
such advantages may be achieved in accordance with any one
embodiment of the disclosure. Thus, the disclosure may be embodied
or carried out in a manner that achieves or optimizes one advantage
or group of advantages as taught herein without necessarily
achieving other advantages as may be taught or suggested herein.
The features of the disclosure which are believed to be novel are
particularly pointed out and distinctly claimed in the concluding
portion of the specification. These and other features, aspects,
and advantages of the present disclosure will become better
understood with reference to the following drawings and detailed
description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The figures which accompany the written portion of this
specification illustrate embodiments and method(s) of use for the
present disclosure constructed and operative according to the
teachings of the present disclosure.
[0014] FIG. 1 is flow chart of a method of forming an
elastomer-algae composite material according to the present
disclosure.
[0015] FIG. 2A is a photograph a final product including an
elastomer-algae composite material of the present disclosure and
produced according to the method of the present disclosure.
[0016] FIG. 2B is a chart of physical properties of final product
10 of FIG. 2A.
[0017] FIG. 2C is a chart of test data for the final product 30 of
FIG. 2A.
[0018] FIG. 2D is a comparison chart of a do different direct algae
content elastomer final solid products.
[0019] FIG. 3 is a photograph of a plurality of experimental
elastomer-algae composite materials produced according to a method
of the present disclosure.
[0020] FIG. 4 illustrates charts showing compression testing and
percent change after fatigue testing of the materials of FIG.
3.
[0021] FIG. 5 illustrates charts showing density and thickness of
the materials of FIG. 3.
[0022] The various embodiments of the present disclosure will
hereinafter be described in conjunction with the appended drawings,
wherein like designations denote like elements.
DETAILED DESCRIPTION
[0023] The present disclosure provides for a composition of matter
and methods to produce sustainable elastomer composite materials
using algae as a bio-based filler. Algae biomass and components of
algae can be derived from both a microalgae and a macroalgae. Algae
biomass includes but is not limited to biomass produced by algae
species. Example algae species include, but are not limited to,
Haptophyta, Cyanophyta, Chlorophyta, Ochrophyta, Rhodophyta, and
Phaeophyta, for example blue-green algae, green algae, diatoms, red
algae, and brown algae.
[0024] In one form, the algae biomass includes a composition of
protein from about 1% to 60%, ash from about 1% to 90%,
carbohydrates from about 1 to 50%, and lipids from about 1% to 30%.
The algae biomass may be washed or fractionated to achieve better
compositions for rubber incorporation, or they may be harvested
with a composition which is well suited for elastomer
incorporation. Due to interactions between protein and sulfur based
curing or vulcanizing agents, a composition which is lower in
protein can be desired since it will improve the processability of
the rubber as well as in some cases the mechanical properties of
the finished goods. In cases in which sulfur curing or
vulcanization is not occurring or in which higher protein content
is favored for its contribution to finished good properties, high
protein composition may be selected. High ash fractions may be
selected when reinforcing characteristics are desired and are
exhibited by organisms like diatoms, coccolithophores, and
coralline algae which are known to biologically produce minerals.
These types of high mineral biomasses can aid in producing results
such as higher abrasion resistance or durability and the algae can
exhibit minerals with a high surface area compared to comparable
mined mineral sources which can aid in foam nucleation and other
characteristics not exhibited by mined minerals in addition to
holding the environmental benefits ascribed to the renewable algae
biomass.
[0025] Referring to FIG. 1, an example of a process 100 for
producing an elastomer-algae composite material is shown. At box
110, process 100 begins by premixing an elastomer matrix in a batch
mixer for a period of time sufficient to plasticize the elastomer
into a suitable condition for mixing. This time can vary depending
on the selection of the elastomer. In an example, the mixing time
is up to about 20 minutes or more.
[0026] The process continues to box 120 where algae filler, which
is formed of algae biomass and can be interchangeably referred to
as algae biomass filler, is added into the batch mixer. The algae
filler can be provided as particles through a milling process or
the like. In some examples, the algae is processed, dried and
converted to particles of a desired size to form the algae filler.
Continuing to box 130, plasticizers and/or other performance
enhancing additives are added to the batch mixer in sufficient
amounts to deliver desired properties of the composite. At box 140,
an elastomer-algae blend is formed by blending the algae and
elastomer in the batch mixer to a temperature sufficient to be
further mixed on a two-roll mill stack. The sufficient temperature
is about 10.degree. C. higher than the temperature sufficient for
the elastomer alone.
[0027] Continuing to box 150, the process includes adding and
mixing in the batch mixer a curing and/or vulcanizing agent for the
elastomer. The amount of curing or vulcanizing agents are provided
in an amount of about 10% to 500% more than sufficient to cure
and/or vulcanize the elastomer absent the algae filler. At box 160,
the process includes dispersing the elastomer-algae blend onto a
two-roll mill stack. The final form is achieved in box 170 where
the heating and curing of the elastomer-algae blend occurs.
[0028] Algae biomass can be prepared according to a variety of
procedures to generate a suitable mixing material, referred to as
the algae filler. In an example, the algae biomass can be milled
such that it has a particle or material size average value of less
than or equal to about 120 microns, including between about 10 and
120 microns, including 15 to 100 microns, and 20 to 80 microns.
Particle size allows for easier incorporation and mixing the algae
filler into an elastomer compound. Additionally, the algae biomass
may be dried to below a desired moisture content such as less than
20% moisture content including less than 15% moisture as well as
less than 5% moisture. In an example, the algae biomass is dried to
about 3% moisture to prevent moisture from interfering with
incorporation of the algae into the elastomer. The desired drying
step can be performed before and/or after the filler forming
step.
[0029] The term "elastomer" is understood to include, but not
limited to any of the following: Natural Rubber (NR), Butadiene
Rubber (BR), Acrylonitrile Butadiene Rubber (NBR), Styrene
Butadiene Rubber (SBR), Hydrogenated Acrylonitrile Butadiene Rubber
(HNBR), Ethylene Propylene Diene Rubber (EPDM), Chloroprene Rubber
(CR), Chlorinated Polyethylene Rubber (CM), Silicone Rubber (Q),
Isoprene rubbers (IR) or combinations thereof.
[0030] Once the algae biomass is sufficiently prepared as an algae
filler for incorporation into an elastomer composite material, the
algae filler is added in an amount ranging from about 1% to 75%
including about 5% to 65% and about 10% to 55% by weight to an
internal batch mixer, such as a BANBURY mixer, with an elastomer
and other plasticizers or performance enhancing additives
sufficient to deliver target properties of the final elastomer
composite. In an example, the algae filler is added after the
elastomer has been premixed for a period of time, which may extend
up to about 20 minutes so that the elastomer is properly
plasticized and more ready to incorporate the algae biomass
filler.
[0031] Elastomer compounds with polar functionalization may be
added to enhance compatibility of the algae filler to the
elastomer. In an example, for NBR or SBR, a carboxylated
acrylonitrile butadiene rubber (XNBR) was used and demonstrated
enhanced compatibility as measured by increases in measured force
exerted on an oscillating disk rheometer. In other examples, polar
elastomers may be grafted with groups that have polarity like a
carboxylated polar elastomer. In yet another example polar
elastomers are grafted with groups including, but not limited to,
acrylonitrile, styrene, or methyl methacrylate groups, or polar
elastomers may have modifications to its chain such as being
epoxidized or having in chain substitutions for more polar
groups.
[0032] In a further example, a thermoplastic compatibilizer, which
may be a grafted, a block chain substituted, or another
thermoplastic polymer, which is well suited to enhance polar
compatibility, may be selected to aid in compatibility between
algae and the elastomer. The compatibilizers can be selected from
those used for polypropylene and polyethylene and their copolymers
with compatibilizers targeting these thermoplastic being effective
for elastomer use. These thermoplastic compatibilizers in some
cases are modified with maleic anhydride, glycidyl methacrylate, or
other polar moieties. Crosslinkers or coupling agents such as
isocyanates, peroxides, or glyoxal may also be used to increase the
compatibility of the algae filler to the elastomer matrix.
Crosslinker selection should be cautious to avoid interference with
curing or vulcanization of the elastomer to prevent a loss in
desired finished product properties.
[0033] Finally, the selected elastomer may have sufficient polarity
to allow for adequate compatibility with algae filler and/or in
some cases increasing compatibility may result in negative impacts
on one or more mechanical properties of a finished product or part.
Accordingly, compatibilizer usage and selection should be decided
upon on the basis of the properties of the desired product targeted
as well as the processing considerations of the elastomer
material.
[0034] If a polar elastomer is used, it can be added during the
elastomer premix to disperse and plasticize with the other
elastomers before the algae biomass is introduced. The algae can
then be blended with the elastomer until it reaches a temperature
which is sufficient for it to be further mixed on a two-roll mill
stack. Sufficient temperature can vary depending on the elastomer
being used. In an example, elastomer-algae blends may need to reach
a temperature of about 10.degree. C. higher than the elastomer
alone due to the impact of the algae biomass on the viscosity of
the elastomer.
[0035] Outside of compatibilizers various process and performance
enhancing aids may be added to an algae elastomer foam to enhance
the physical properties and/or processability of the
algae-elastomer blend. These may include waxes, oils, plasticizers,
thermoplastics, mineral fillers, bio-fillers, pigments,
accelerators, antioxidants, flame retardants, and
surfactants/wetting agents. Selection and usage of these processing
or performance enhancing aids can be done by one skilled in the art
of finished rubber goods manufacturing based on the needs of the
product.
[0036] Once the elastomer-algae blend has been sufficiently mixed,
it can be further dispersed by running through a two mill roll
stack and being folded over onto itself. After being sufficiently
dispersed through layering on the two-mill roll stack, the
elastomer-algae blend can be stored until ready for use. Prior to
storage the algae-elastomer composite may be added to a single
screw extruder and extruded through a die and pelletized in order
to make packaging, handling or storage easier.
[0037] An algae elastomer batch may also be loaded with more algae
filler than the quantity of algae desired in a finished good such
that an algae elastomer composite masterbatch is created. A
masterbatch may be useful in allowing the composite to be made and
used in different locations without incurring as significant
shipping and environmental drawbacks and it is also useful in
serving the needs of many products at once if they are sufficiently
similar that the their final formulations can be achieved in the
mixing step before use allowing masterbatches to be made with
greater economies of scale in production. A masterbatch in most
cases will have greater algae contents than is intended in an end
or finished product since it is intended to be let down and, in an
example, includes up to 75% algae content by weight including up to
60% algae content by weight and up to 40% algae content by weight.
In yet a further example, the algae content of the masterbatch is
between 1% and 75% by weight including 10% to 75% by weight. In
addition, in certain cases a thermoplastic may be blended with
algae to create a masterbatch which can be let down into the
elastomer blend. Thermoplastic masterbatches can have the
advantages of being made on extruders which can have improved
mixing and run continuously, however, thermoplastics do not exhibit
the same properties as elastomers, and therefore in many cases a
loss of properties will result when using thermoplastic
masterbatches.
[0038] While Banbury mixers and two mill roll stack mixing is the
most common route to mix and disperse materials in elastomer
manufacturing any mixer which is suitable for plasticizing the
elastomer and introducing and dispersing a powder in the elastomer
may be used. This may include but is not limited to single
extruders, twin screw extruders and other mixing equipment used in
processing rubbers.
[0039] When ready for production, the elastomer-algae blend
(masterbatch) is added back into an internal batch mixer to
introduce curing and vulcanizing agents for the elastomer. Due to
interference with these agents from the algae, it is typical to see
relatively higher doses of these agents being added to achieve a
desired result. In an example, 10% to 500%, including 25 to 300%
and 50 to 200% more of these agents will allow curing and/or
vulcanizing to occur as desired. If an elastomer algae masterbatch
is being used, in addition to vulcanizing and curing agents, more
elastomer material will likely be added in a mixing step before the
product is used. This mixing step may be the same as the step
introducing curing and vulcanizing agents or it may be conducted as
a separate step.
[0040] After mixing is finished, the elastomer-algae blend is
further dispersed on the two-roll mill stack through folding the
material over onto itself and layering it. The two-roll milling
process often requires around 10.degree. C. higher temperatures to
properly disperse the material due to the viscosity changing
effects of the algae with the degree of temperature change required
depending on the amount of algae present.
[0041] After the two-roll mill stack, the elastomer-algae blend is
ready to be heated and cured into a finished part or end product.
The heating and curing process may take many forms. For example, in
one form, an extruder may heat, mix, and extrude the material and
then it may be passed through a heating tunnel in which it is cured
and foamed into an elastomer-algae composite foam sheet. In yet
another form, the resulting elastomer-algae composite may be rolled
into flat sheets and then applied to molds where it is pressed into
a form and then heated and cured into a desired finished product,
such as a shoe outsole or other shoe component. The elastomer-algae
blend material can be shaped and heated in the final processing
step to generate the desired form to service a desired market using
conventional processing methods. In some examples, little to no
modifications to the conventional processing conditions are
needed.
[0042] The present disclosure further provides for an elastomer
foam material that includes algae. In the example of an elastomer
foam such as that which might be used in insulation, gasket and
seals, sound abatement, anti-fatigue mats and other applications,
the addition of a foaming agent and in some cases, accelerants are
used to produce the foam. The foaming agents and accelerants are
added along with the curing and vulcanizing agents in the last
mixing step via an internal batch mixer so as to ensure there is no
early evolution of gas from the rubber material. Foaming agents and
accelerants are added so as to yield the appropriate degree of
foaming and have the foaming onset occur after sufficient curing
has occurred in the material to allow for gas entrapment.
[0043] Accelerant loading and temperatures required to foam will
depend on the elastomer being foamed, but the addition of algae can
in some cases cause higher temps to be reached for proper curing
before foaming onset should occur. This phenomenon can be offset to
some degree through the use of compatibilizers and the proper
loading of curing agents and accelerants to balance between curing
rate and foaming rate. Foaming agent selection and loading depends
on the elastomer being used and the desired properties of the foam,
however, in at least some cases, foaming agents make up 1 to 30% of
the formula including 2 to 25% and 5 to 20% by weight. The algae
can serve as a nucleating agent for bubble formation especially
mineralized algae, but additional nucleating agents may be used if
desired. Additional algae in a rubber foam may create an open cell
structure which is beneficial in some circumstance so long as it
does not create a loss in desired properties such as compression.
Additionally, the incorporation of low levels of algae into
elastomer foam goods has been shown to improve compression set
properties which is a critical property in foam performance.
[0044] In an example of a solid rubber good such as might be found
in shoe soles, grips, automotive parts, hosing, tires, and other
products, algae-elastomer blends can be used using conventional
compression molding processing techniques. The algae-elastomer
blends can rolled flat into sheets or be cut or otherwise shaped
into pre-forms, which are then placed in molds, which are then
closed and subjected to sufficient heat and pressure to cure the
rubber and form a finished part or good. When algae is present,
longer times spent curing in the molds may be desired, but are not
required if performance requirements are met without longer cure
times.
[0045] Similar techniques may be used for transfer molding.
Injection molding of elastomers and calendaring of elastomers are
also envisioned with standard industry techniques being suitable
for the algae elastomer blends of the present disclosure, and only
minor condition changes being necessary to produce finished parts
or goods which meet industry expectations. These condition changes
will likely attempt to address the viscosity changes and cure time
and temp changes that the use of algae in rubber introduces.
[0046] In solid elastomer goods, algae has been shown to reinforce
the elastomer finished goods contributing to significant
improvement in structural characteristics and measures of toughness
such as tear strength. Non-mechanical benefits may exist in some
cases due to increases in surface polarity and Gibbs free energy
which can affect the finished goods interactions with solvents,
adhesives, grip characteristics, and other unique benefits.
[0047] Referring to the examples of FIGS. 2A, 2B, 2C and 2D, a
plurality of shoe components (10, 20, and 30) is shown and formed
according to a method of the present disclosure. These examples
show a solid elastomer algae composite material. The shoe
components include a first shoe component 10 of a relatively
thinner smaller size. In this example, component 10 can be an
insole or midsole. Shoe component 20 is a larger shoe component as
compared to component 10 and includes a textured bottom surface
which can be used as an outsole. Shoe component 30 is still larger
relative to shoe components 10 and 20 and also serves as an outsole
with a textured bottom like outsole component 20. All three
components include an elastomer-algae composite material of the
present disclosure. A chart illustrating resulting properties of
component 10 is shown in FIG. 2B to illustrate that a 15% algae
content by weight is feasible in an elastomer composite. In this
example, the component included a masterbatch which includes both
algae and thermoplastic. Shoe components 10, 20 and 30 exhibit
certain desired results of properties including tear, specific
gravity (SG), split tear, and abrasion strength along with hardness
and elongation data. FIG. 2C illustrates a chart of test results
for component 30 to identify properties of the component. FIG. 2D
shows a comparison table of a 10% algae elastomer composite against
a 5% algae elastomer composite. In this example, the dry slip and
wet slip characteristics will be impacted by the shape, size, and
texture of the final end product. Moreover, using an
elastomer-algae composite product has important environmental
benefits and reduces the reliance on fossil fuels.
[0048] FIGS. 3-5 illustrate a control elastomer foam sample 50 that
includes elastomer without algae, and example elastomer-algae foam
composite materials 51, 52, 53, 54, and 55, produced according to
the present disclosure. These materials were labeled and tested and
shown in a stack in FIG. 3. A control sample 50, is shown
positioned on top of a stack that includes samples 51, 52, 53, 54,
and 55. These samples were used to illustrate that the various
algae containing materials resulted in close to equal, equal,
and/or improved physical properties, particularly related to
compression deflection at 25% psi and after 2000 and 4000 fatigue
cycles. In these examples, the control sample 50 includes elastomer
with no algae. Sample 51 through 55 are from a factorial design
experiment looking at particle size, protein to mineral ratio, and
compatibilizer loading to establish best conditions for desired
foam properties. Large particles had an average particle size of
around 70-80 micron and small particle samples had an average
particle size of around 25-35 micron. The labeling of the
components are defined as: LP-HA/LP=Low Protein, High Ash, Large
Particles; HP-LA/SP=High Protein, Low Ash, Small Particles;
LP-HA/SP=Low Protein, and High Ash, Small Particles. The percentage
relates to compatibilizer loading. Sample 51 includes LP-HA/LP/2%,
sample 52 includes HP-LA/SP/2%, sample 53 includes LP-HA/LP/4%,
sample 54 includes LP-HA/SP/4%, and sample 55 includes LP-HA/SP/2%.
Moreover, the percentage change after fatigue testing also was
reduced for algae containing materials as shown in FIG. 4. FIG. 5
illustrates how density can be increased while reducing thickness
as compared to the control state 50. Up to 20% algae content has
been demonstrated in similar foams to those shown in the
figures.
[0049] It should be noted that the steps described in the method of
use can be carried out in many different orders according to user
preference. The use of "step of" should not be interpreted as "step
for", in the claims herein and is not intended to invoke the
provisions of 35 U.S.C. .sctn. 112 (f). Upon reading this
specification, it should be appreciated that, under appropriate
circumstances, considering such issues as design preference, user
preferences, marketing preferences, cost, structural requirements,
available materials, technological advances, etc., other methods of
use arrangements such as, for example, different orders within
above-mentioned list, elimination or addition of certain steps,
including or excluding certain maintenance steps, etc., may be
sufficient.
[0050] The embodiments of the disclosure described herein are
exemplary and numerous modifications, variations and rearrangements
can be readily envisioned to achieve substantially equivalent
results, all of which are intended to be embraced within the spirit
and scope of the disclosure. Further, the purpose of the foregoing
abstract is to enable the U.S. Patent and Trademark Office and the
public generally, and especially the scientist, engineers and
practitioners in the art who are not familiar with patent or legal
terms or phraseology, to determine quickly from a cursory
inspection the nature and essence of the technical disclosure of
the application.
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