Fungal mycelium and cotton plant materials in the manifacture of biodegradable molded packaging material
1. Fungal Mycelium and Cotton Plant Materials in the
Manufacture of Biodegradable Molded Packaging Material
Article by: G. A. Holt, G. McIntyre, D. Flagg, E. Bayer, J. D.
Wanjura, and M. G. Pelletier
Presented by: Colby Cofield
2. Introduction
• Styrofoam (Polystyrene) products
• Used in product packages and the shipping industry
• The world produces tons of it each year.
• Hydrophobic, resistant to photolysis, Non-Biodegradable
• attractive to shippers and packing industries
• Alternative substitutes for packing and insulation?
• economically viable, environmentally friendly replacement for polystyrene packaging
materials.
• a composite containing fungal species on agricultural biomass
3. Background
• Renewable Crops
• Renewable crops and their agricultural residues enhance the properties of composite
structures
• Fungal Cultivation
• Fungi has been used to manufacture environmentally friendly products
• Combine them?
• improve bonding properties
• Objective:
• Develop six blends of processed cotton plant material
• Produce a packaging material and subject it to standard test methods
4. Materials and Methods
• Cotton Plant Biomass and Blends
• By-product of harvesting,Cotton carpel (bur), obtained
from the extractor of a cotton gin
• Removes about 55% of the total waste stream before gin
• Carpels processed through a hammer-mill or attrition
mill
• Then sorted across a vibratory conveyer
• Particle size: 0.1 to 51 mm
• Sized material was stored until blending.
5. Materials and Methods
• Blending
• Using a ribbon mixer
• Constituent material used in all six blends:
• Processed Cotton Carpel
• Cotton seed hull,
• Starch, and
• Gypsum
• Variable particle size
• Ingredient's added into the mixer and agitated
• 1.5 to 2.5 L of water added
• Blend was mixed for 7 minutes at max agitation (15 rpm). Fig 2. Auger
6. Materials and Methods
• Composite Fabrication
• Blends emptied into an auger that fed a pasteurizer.
• 115°C for 28 min.
• Gravity fed to Cooler (35°C)
• Inoculation with fungus (grain or liquid substrate)
• Ganoderma sp.
• Discharged into plastic mold (tool)
• Sealed to maintain consistent micro-environment
Fig 4. Selecting the lid for the tool containing inoculated cotton plant material
substrate (left) and snapping the lid in place (right) to maintain micro-
environment for optimum growth.
Fig. 3. Schematic used to produce the cotton plant and fungal mycelium based
molded packaging specimens evaluated in this study.
7. Materials and Methods
• Incubation and Heating
• Filled tool was incubated at 21°C for 5 days
• Fungal mycelium colonizes the blend
• Part was removed from tool and placed in a 60°C oven
for 8 hours.
• Inactivated fungus and prevented reanimation
• After Drying, stored in ambient conditions
• 21°C and 30% Relative Humidity
Fig 6: Finished fungal mycelium molded packaging
piece after drying
Fig 5:Time sequence showing the inoculated cotton plant material substrate (day 0) and fungal
colonization over a 3-day period.
8. MaterialsAnd Methods
• AnalyticalTesting
• StandardTest Methods:
• Compressive Strength
• Flexural Strength
• modulus of elasticity
• density
• dimensional stability
• accelerated aging
• water absorption
• cone calorimetry
• thermal conductivity
• They did not evaluate expanded polystyrene samples in this
study.
• Data Analysis
• Two types of inoculum (grain and liquid substrate)
• Applied to each of the cotton plant material blends (12 total treatments)
• Honestly Significant Difference
Fig 7. Flexural strength testing of one of the cotton plant
material test specimens.
Fig 8. Cone calorimeter test samples of two of the treatments
evaluated in this study,Grain 6 (left) and Grain 4 (right), after
testing.
9. Results and Discussion
• Physical Properties
• Dimensional stability after drying
• Grain-based blends show less surface
area contraction
• Smallest surface area contraction
• Grain 3 (Blend 3) at 0.64%
• Greatest surface area contraction
• Liquid 5 (Blend 3) at 2.4%
• Importance of Dimensional Stability
• Tool design specification
Fig 9.Average surface area contraction (%) or shrinkage of the sample pieces made from each
treatment after oven drying. Bars with the same letters are not significantly different at the 0.05 level
of significance.
10. Results and Discussion
• ContractionVariability
• More variable blend combinations = less consistency
• All treatments had similar standard mean errors
associated with percent contraction (0.093 to 0.108)
• FS, EM, and CS
• Flexure Strength, Elastic Modulus, and Compressive
Strength are normalized to a standard density of
32.04 kg/m3
• Grain 1 had the most consistent performance
• lowest degradation values for FS, EM, and CS compared
to all other treatments.
11.
12. Results and Discussion
• Water Absorption
• The largest increase in water absorption from
0.75 hr to 3 hr
• Liquid 4 from 11.2% to 39.2%
• Smallest increase
• Grain 4, 8.9% to 12.2%
• Largest Absorption
• Grain 1 (198%)
13. Results and Discussion
• Thermal Properties:
• Thermal Resistance:
• Highest R-value: Liquid 6 (1.5)
• Thermal conductivity (property to conduct heat)
• Highest with Grain 3 (0.18) and Lowest with Liquid 6 (0.10)
14. Results and Discussion
• Cone Calorimetry – (mass loss)
• Showed gas production (CO and CO2) for Grain 6 to have
significantly higher production than all other treatments.
• 51 mg/s – CO and 2428 mg/s- average CO2
• Lowest CO gas production was Liquid 3 (0.9 mg/s)
• The average CO production for Grain 1, Grain 4, and
Grain 5 show zero emissions when in actuality they are
less than 0.00 mg/s.
• Liquid 3 had significantly lower mass loss (8.8 mg/s)
• Average for all others (65% mg/s)
15. Application of Findings
• Cotton-based fungal mycelium packaging material is a
viable alternative.
• Figure 10 (left) is an application using Grain 1 and 2
• Figure 11 (right) is a hybrid
Fig 10 and 11. Fungal mycelium and cotton plant material molded packaging material being used by a large office equipment
manufacturer in the United States.
16. Conclusion
• Cotton-based biomass blends
• Two methods, grain and liquid, were used to inoculate the six cotton based blends with
fungal spores
• Liquid inoculum
• Consistent distribution of fungal spores
• Grain inoculum higher densities
• Higher than desired (32.04 kg/m3)
• Future Reference
• Cotton plant material > 2mm diameter
• No outperformers, most performed similarly
17. Conclusion
• Percent Degradation (w/ accelerated aging)
• Grain 1 was most consistent in maintaining FS,CS, and EM
• Cotton-based fungal mycelium packaging material is a viable alternative to
polystyrene packaging
• Refinements in processing and biomass blend development
• Product improvements
• Improved physical characteristics
• Cause agricultural residue-based fungal composites to be suitable for numerous
applications
18. References
• Holt, G.A., McIntyre, G., Flagg, D., Bayer, E., Wanjura, J.D., Pelletier, M.G., 2012.
Fungal mycelium and cotton plant materials in the manufacture of biodegradable
molded packaging material: evaluation study of select blends of cotton
byproducts. J. Biobased Mater. Bio. (in press).
• http://www.sciencedaily.com/releases/2009/08/090819234651.htm. August 20
(2009).Verified June 2011.
• https://dir.indiamart.com/ahmedabad/ribbon-blender.html December 20 (2011).
• ASTM C165-07, StandardTest Method for Measuring Compressive Properties fo
Thermal Insulations, ASTM International (2007).
• http://www.universalconstructionfoam.com/downloads/eps-data-sheet.pdf
22. MYCELIUM BASED ACOUSTIC ABSORBERS GROWN ON
AGRICULTURAL BY-PRODUCT SUBSTRATES
• The new material being tested is based on a fungi that is grown on semi-hydrophobic agricultural byproduct
• substrates such as switch-grass, rice straw, sorghum stalks, flax shive, kenaf and hemp.
• The testing of the material for use in acoustics utilized an impedance tube and measured the standing wave
ratios
Editor's Notes
With the rise of companies like amazon and Walmart supporting more and more online orders, Packaging plays an important role in ever order.
The most common packaging material used in the market today is Styrofoam
Styrene leaches into foods and drinks and Styrofoam releases large amounts of ozone into the atmosphere, causing respiratory and environmental issues.
Since polystyrene is non-biodegradable, a biodegradable material that is eco-friendly is being sought as a substitute for packaging and insulation board consumers
One such process, involves growing fungal species on agricultural biomass to produce an ecofriendly packaging product
the packaging material evaluated
By growing the mycelium around agricultural by-products,the by-products provide food and a base structure for the fungi which in turn provides the binder to form the agricultural by-products into molded shapes that are low cost and suitable for such applications as packing material for shipping as well as construction insulation in a manner that is competitive to more traditional particle board composites built using rice-straw and other agricultural by-products such as composites
The mycelium provides structural binding properties for the mixture through the growth of interconnecting fibrous threads that form chitin and Beta Glucan based structural oligosaccharides that bind the bulk agricultural materials into a composite board or complex shape capable of replacing non-renewable resource materials such as Styrofoam and poly-urethane foams
An oligosaccharide is a saccharide polymer containing a small number of monosaccharides. Oligosaccharides can have many functions including cell recognition and cell binding
Literature Review of the properties of polystyrene
The combination of ag residues and fungi have been evaluated for fungal cultivation
And have proved to improve bonding properties of fibers within the composites
A company has developed processes that involve growing fungal species on agricultural residues, such as cotton plant material, to produce an environmentally-friendly packaging material.
Standard test methods to test for compressive strength, flexural strength, modulus of elasticity, density, dimensional stability, accelerated aging, water absorption, cone calorimetry, and thermal conductivity.
The mycelium provides structural binding properties for the mixture through the growth of interconnecting fibrous threads that form chitin and Beta Glucan based structural oligosaccharides that bind the bulk agricultural materials into a composite board or complex shape capable of replacing non-renewable resource materials such as Styrofoam and poly-urethane foams
An oligosaccharide is a saccharide polymer containing a small number of monosaccharides. Oligosaccharides can have many functions including cell recognition and cell binding
The cotton plant material used in this study was a byproduct of typical mechanical harvesting and ginning practices in the United States which generate approximately 2.5 Mg of cotton byproducts across the U.S. cotton belt each year
Which is equal to 2200 pounds of excess material a year.
The process started with the waste-products of the cotton gin, cotton carpel and sticks.
(on a cotton gins agricultural waste system)
Conveyor (to obtain specific particle size ranges needed for each blend in table 1)
Carpel
the female reproductive organ of a flower, consisting of an ovary, a stigma, and usually a style.
Blending
The constituent materials used in the six blends evaluated were comprised of
1. processed cotton carpel
2. cotton seed hull
They occasionally are included in grain mixes to increase the bulk density and crude fiber content.
3. starch,
Help the internal Strength
4. gypsum
gypsum can also be used: As a soil additive (sometimes called land plaster) to improve the soil's workability and receptivity to moisture, and to overcome the corrosive effect of alkalinity
Ingredients added one at a time
The primary ingredient was the processed cotton carpel.
For all six blends, the percent of ingredients was the same for all
Each ingredient was added one at a time into the mixed and agitated while adding between 1.5 to 2.5 L of water, to minimize dust and promote adhesion of the starches and gypsum to the cotton plant material.
After completed, the blend was emptied into tote bags, and labeled and stored.
Composite Fabrication
fed a pasteurizer where the material was sterilized at 115°C for 28 min.
COOLER WAS A water jacketed auger (cooler) where it was cooled below 35°C.
grain or liquid substrate as the carrier.
Tool was in desired shape of the piece to be fabricated.
Material was gently hand-packed in the tool and any excess was removed.
consistent micro-environment for fungal propagation. (Figure 3)
Incubation and Heating
Figure 5 shows the fungal colonization of one of the blends over a 3 day period
After 5 days, the part was removed from the tool and placed in 60°C convection oven for 8 hours, which
After Drying, the pieces were stored at ambient laboratory conditions (21°C and 30%RH (Relative Humidity) until testing.
Figure 6 shows a typical part after drying
Specifics related to quantity of inoculum, pasteurizer and cooler speeds, and specific processes applied not listed are considered proprietary information.
Analytical Testing
Cone Calorimetry (flame retardance characteristics) was performed at the Worcester Polytechnic Institute (WPI) Fire Research Laboratory in MA.
Specimens were tested in horizontal orientation at 50 kW/m^2 heat flux.
All other analyses were conducted at Ecovative labs.
Data Analysis
each treatment was replicated 3 to 12 times depending on the test method and property being evaluated.
Standard analysis of variance techniques were used to analyze the data to determine statistically significant differences among the 12 treatments by the HSD (Honestly Significant Difference) test at the 95% confidence level.
Similar to the t-test
Except accounts for error in data grouped together simliar
Dimensional stability = surface area contraction
Blends inoculated with the grain-based substrate showed less surface area contraction than did blends inoculated with the liquid-based substrate
Grain 3, 4, 5, and Liquid 6 were similar in the percent contraction and significantly lower than Grain 2, Liquid 1, 2, 3, 4, and 5
The importance of dimensional stability is related to tool design.
The larger the percent contraction the more oversized the tool needs to be for the finished product to be within desired specifications
The more variable a blend/inoculum combination is, the more difficult it is to produce parts that are consistently within dimensional tolerances of customer specifications
All treatments had similar standard mean errors associate with percent contraction (0.093 to 0.108), so the means are a reliable indicator of the contraction expected when designing tools for a given treatment
Flexural Strength = bend strength
Represents the highest stress experience within the material at its moment of yield
FS degradation grain 5,1,6 and liquid 3 exhibited little degradation from aging.
Liquid 5’s FS was reduced almost in half as a result of aging
Grain 3 and Liquid 2 exhibited increased stiffness due to aging
Elastic Modulus
is a number that measures resistance to being deformed elastically (i.e., non-permanently)
Compressive Strength
the resistance of a material to breaking under compression.
Overall, Grain 1 had the most consistent performance, by
exhibiting some of the lowest degradation values for FS, EM, and CS compared to all other treatments.
Degradation Percentage = (Conditioned test value/as received test value) ∗ 100
The density of the treatments ranged from 66.5 kg/m3 to 224 kg/m3
The density for grain treatments was higher than for the liquid treatments due to the greater mass of the grain-based inoculum versus the liquid-based inoculum
FS EM CS
Standardized to the density of the polystyrene packaging that can be replaced in the market
Flexural Strength = bend strength
Represents the highest stress experience within the material at its moment of yield
FS degradation grain 5,1,6 and liquid 3 exhibited little degradation from aging.
Liquid 5’s FS was reduced almost in half as a result of aging
Grain 3 and Liquid 2 exhibited increased stiffness due to aging
Elastic Modulus
is a number that measures resistance to being deformed elastically (i.e., non-permanently)
Compressive Strength
the resistance of a material to breaking under compression.
Overall, Grain 1 had the most consistent performance, by
exhibiting some of the lowest degradation values for FS, EM, and CS compared to all other treatments.
Degradation Percentage = (Conditioned test value/as received test value) ∗ 100
After 3 h, Grain 1 (48.0%) still had the highest water absorption and Grain 6 (10.8%) the lowest
The largest increase in water absorption from 0.75 h to 3 h was seen in Liquid 4 which moved from 11.2% to 39.2%
The smallest increase from 0.75 h to 3 h was Grain 4, 8.9% to 12.2%.
The largest absorption, after 168 h, was seen in Grain 1 (198%) with the lowest percent absorption in Grain 3 and Grain 6, 93.5% and 94.3%, respectively
R value is a materials resistance to conductive heat flow
The higher the R-value the greater the insulating effectiveness
Thermal conductivity
Property of a material to conduct heat
The conductivity values were within the ranges of gypsum, plywood, hardwood, and softwoods
They thought the data was an error in data entry or mistake analyzing the data but the data was validated by doing further testing.
investigation into the interaction of substrate particle size and method of inoculation to cone calorimeter analysis.
With the exception of Grain 6, all other treatments had average CO production less than 1.0 mg/s.
The peak and average CO2 production was lowest for Liquid 3 (237.8 mg/s—peak; 151.6 mg/s— average) and Grain 2 (310.1 mg/s—peak; 144.6 mg/s— average).
Cone calorimeter testing showed Liquid 3 had the smallest mass loss (8.8%) compared to Liquid 4 with 74%. Liquid 3 had significantly lower mass loss than all treatments except Grain 3 (52.7%), Liquid 1 (46.2%), and Liquid 6 (39.5%). The peak and average mass loss rate were lowest for Liquid 2, 76.7 mg/s and 1.5 mg/s, respectively. The highest peak and average mass loss rates were seen in treatments Grain 1 (153.3 mg/s—peak) and Liquid 3 (71.4 mg/s—average).
Viable alternative to polystyrene packaging.
show two commercial applications for the type of products produced from two blends evaluated in this study.
This study evaluated cotton-based biomass blends for use in a process designed to produce an environmentally-friendly molded packaging material that could replace polystyrene packaging (currently in the marketplace).
In addition to the six-cotton based blends, two methods, grain and liquid, were used to inoculate the blends with fungal spores resulting in twelve treatments.
Meaning twelve different variations to work with
The liquid inoculum was easier to use in the process and
provided a more consistent distribution of fungal spores when applied to the blends.
The grain inoculum generally resulted in higher densities due primarily to the added weight of the grain
due in large part to the inclusion of cotton plant particles less than 2 mm
To avoid problems in the future, cotton plant material having a diameter less than 2 mm will not be used.
No single treatment outperformed the other treatments in all categories evaluated.
Most of the treatments performed similarly to each other for the response variables measured.
Improved physical characteristics will cause agricultural residue-based fungal composites to be suitable for numerous applications that presently use fossil-fuel based materials
As refinements in processing and biomass blend development continue, the physical and mechanical properties of the product should improve
Improved physical characteristics will cause agricultural residue-based fungal composites to be suitable for numerous applications that presently use fossil-fuel based materials
By growing fungi around agricultural by-products, the by-products provide food and a base structure for the fungi which in turn provides the binder to form the agricultural by-products into molded shapes that are low cost and suitable for such applications as packing material for shipping as well as construction insulation in a manner that is competitive to more traditional particle board composites built using rice-straw and other agricultural by-products such as composites
Summarize the main points of your presentation
Suggest future avenues of research
Mycelium based boards showed promise in providing an alternative .
CITE PICTURE
TAKE DATA IN ORDER AND COMPARE
They ran tubes through the material that simulated the excitation (vibrations) road noises
Testing how well different materials were as acoustic absorbers.
The testing of the material for use in acoustics utilized an impedance tube and measured the standing wave ratios
The new material being tested is based on a fungi that is grown on semi-hydrophobic agricultural byproduct substrates such as switch-grass, rice straw, sorghum stalks, flax shive, kenaf and hemp.
The results of the study show the mycelium based boards are a promising bio-based composite alternative to standard traditional foam insulation board.
Results suggest an optimal performance at the key automotive road noise frequency of 1000 Hz
A further advantage provided by this new material is that it can be produced economically in comparison to the traditional petroleum based foams with the further advantage of bio-degradation when the product is disposed of at its end-of-life use.
