ARE "NATURAL" POLYMERS PLANT-DERIVED POLYMERS? - CONSUMERS PERSPECTIVES
1. Sustainable Plastics 2023
05.08.23 Kiersten Muenchinger, University of Oregon Product Design
Are “Natural” Polymers Plant-Derived
Polymers?
2. Agenda
• Introduce polymer cups and word-pairs
• Present experimental results
• Highlight insights into perceptions of sustainability
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
3. Agenda
• Introduce polymer cups and word-pairs
• Present experimental results
• Highlight insights into perceptions of sustainability
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
4. From left to right:
HDPE/sugar, HDPE/petroleum,
composite Cellulose+PP/trees+petroleum, copolyester/petroleum,
PLA/corn, PP/petroleum
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
5. From left to right:
HDPE/sugar, HDPE/petroleum,
composite Cellulose+PP/trees+petroleum, copolyester/petroleum,
PLA/corn, PP/petroleum
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
6. Okala LCA Impacts:
• Material + Manufacture shows the environmental impact of each
fabricated cup
• Lowest impact product is made of HDPE derived from petroleum
05.08.23
Material Cup Weight
in g (oz)
Okala Material
Impact Factor in
points/lb
Okala Impact Factor,
Material + Manufacture
(injection molding)
Percentage increase in
Impact from HDPE
(petroleum)
HDPE (petroleum) 77.1 (2.72) 1.7 0.411 0
HDPE (sugar) 77.7 (2.74) 1.7 0.414 0.73
PP 72.0 (2.54) 1.9 0.416 1.2
Cellulose/PP 88.2 (3.11) 1.9 (use PP) 0.50 22
PLA 108 (3.80) 1.9 0.622 51
Copolyester 101 (3.55) 3.6 0.959 133
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
7. 05.08.23
Kansei Word Pairs
Durable Delicate
Degradable Lasting
Raw Finished
Harmless Toxic
Natural Artificial
Recyclable Waste
1 2 3 4 5 6 7
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
8. Agenda
• Introduce polymer cups and word-pairs
• Present experimental results
• Highlight insights into perceptions of sustainability
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
9. Average rankings of six cups:
• Durability a sustainability asset of polymers
• Cups made with polymers derived from plants are
generally perceived as more sustainable
05.08.23
1.00
2.00
3.00
4.00
5.00
6.00
7.00
PES/petroleum HDPE/petroleum PP/petroleum HDPE/sugar PLA/corn Cellulose/trees,
PP/petroleum
Durable
Degradable
Natural
Raw
Harmless
Recyclable
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
Copolyester/petroleum
10. Average rankings of six cups:
• Durability a sustainability asset of polymers
• Cups made with polymers derived from plants are
generally perceived as more sustainable
05.08.23
1.00
2.00
3.00
4.00
5.00
6.00
7.00
PES/petroleum HDPE/petroleum PP/petroleum HDPE/sugar PLA/corn Cellulose/trees,
PP/petroleum
Durable
Degradable
Natural
Raw
Harmless
Recyclable
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
Copolyester/petroleum
11. Agenda
• Introduce polymer cups and word-pairs
• Present experimental results
• Highlight insights into perceptions of sustainability
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
12. Sugar-based HDPE cup and Petroleum-based HDPE cup:
• These two cups are the same material
• Qualitatively high similarity in weight, dimensional size,
color, tactility and opacity
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
13. HDPE: Petroleum-derived compared to Sugar-derived, average rankings
• Sugar-derived HDPE cup perceived as more sustainable
in 5 of 6 categories
• These 5 are statistically significant differences; alpha level = .05
05.08.23
1.00
2.00
3.00
4.00
5.00
6.00
7.00
Durable Degradable Natural Raw Harmless Recyclable
HDPE/petroleum
HDPE/sugar
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
14. HDPE: Petroleum-derived compared to Sugar-derived, box plots
• Mean rankings for Degradable, Natural and Harmless
perceptions are lower for the sugar-derived HDPE cup
05.08.23
1
2
3
4
5
6
7
Durable Degradable Natural Raw Harmless Recyclable
Durable Degradable Natural Raw Harmless Recyclable
HDPE/petroleum
HDPE/sugar
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
15. Okala LCA details
05.08.23
Material Cup Weight
in g (oz)
Okala Material
Impact Factor in
points/lb
Okala Impact Factor,
Material + Manufacture
(injection molding)
Percentage increase in
Impact from HDPE
(petroleum)
HDPE (petroleum) 77.1 (2.72) 1.7 0.411 0
HDPE (sugar) 77.7 (2.74) 1.7 0.414 0.73
PP 72.0 (2.54) 1.9 0.416 1.2
Cellulose/PP 88.2 (3.11) 1.9 (use PP) 0.50 22
PLA 108 (3.80) 1.9 0.622 51
Copolyester 101 (3.55) 3.6 0.959 133
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
16. Sugar-based HDPE cup and Petroleum-based HDPE cup:
• Qualitatively insignificant sensorial differences
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
17. Agenda
• Introduce polymer cups and word-pairs
• Present experimental results
• Highlight insights into perceptions of sustainability
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
18. Average rankings of six cups:
• Cellulose/PP composite cup perceived more sustainable
than peers in 5 of 6 categories
• These are statistically significant differences; alpha level = .05
05.08.23
1.00
2.00
3.00
4.00
5.00
6.00
7.00
PES/petroleum HDPE/petroleum PP/petroleum HDPE/sugar PLA/corn Cellulose/trees,
PP/petroleum
Durable
Degradable
Natural
Raw
Harmless
Recyclable
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
Copolyester/petroleum
19. Cellulose/PP composite cup:
• Visual differences: color and texture
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
20. Average rankings of six cups:
• Copolyester and PLA perceived as more durable than Cellulose/PP
• These are statistically significant differences; alpha level = .05
05.08.23
1.00
2.00
3.00
4.00
5.00
6.00
7.00
PES/petroleum HDPE/petroleum PP/petroleum HDPE/sugar PLA/corn Cellulose/trees,
PP/petroleum
Durable
Degradable
Natural
Raw
Harmless
Recyclable
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
Copolyester/petroleum
21. Copolyester and PLA cups:
• Comparative weight may influence perception of durability
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
22. Okala LCA details
05.08.23
Material Cup Weight
in g (oz)
Okala Material
Impact Factor in
points/lb
Okala Impact Factor,
Material + Manufacture
(injection molding)
Percentage increase in
Impact from HDPE
(petroleum)
HDPE (petroleum) 77.1 (2.72) 1.7 0.411 0
HDPE (sugar) 77.7 (2.74) 1.7 0.414 0.73
PP 72.0 (2.54) 1.9 0.416 1.2
Cellulose/PP 88.2 (3.11) 1.9 (use PP) 0.50 22
PLA 108 (3.80) 1.9 0.622 51
Copolyester 101 (3.55) 3.6 0.959 133
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
23. • Disclosing plant-based polymer derivations positively
influences perceptions of polymer product sustainability.
05.08.23
Are “Natural” Polymers Plant-Derived Polymers?
Kiersten Muenchinger, University of Oregon Product Design
Hello
I’m Kiersten Muenchinger
I’m an Associate Professor of Product Design at the University of Oregon
The goal of this study is to guide designers in developing products that consumers emotionally connect with as having environmentally friendly attributes.
The hypothesis for this work is that disclosing plant-based derivations of polymers, such as polylactic acid, or PLA, derived from corn, would positively influence peoples’ perceptions of the “natural-ness” of that polymer, and consequently positively influence peoples’ perceptions of that polymer’s sustainability.
There is an existing consumer trend demanding "natural" materials and products
Natural is undefined, so what if we look at "plant-based" materials for products
Study of products made from polymers derived from petroleum, sugar, corn, and wood
My agenda is to:
First, introduce the polymer cups and word-pairs used in this study.
Second, to present the experimental results found from the participants.
And Third, to highlight insights into perceptions of sustainability for these materials.
First, I will introduce the polymer cups and word-pairs used in this study.
The products used in this study are drinking cups. Drinking cups are used because they are immediately understood products that are commonly made from many different types of material.
These cups are fabricated specifically for this research. They are injection molded, and all come from the same injection mold.
Colorants and other additives are not used.
The cups are made of six different polymers.
The cups are made of six different polymers.
From left to right, they are:
High Density Polyethylene, derived from sugar
High Density Polyethylene, derived from petroleum
A polymer composite of 30% Cellulose, derived from trees, and 70% Polypropylene, derived from petroleum
Copolyester, derived from petroleum
Polylactic Acid, derived from corn
and Polypropylene, derived from petroleum
These polymers are intentionally selected for this study, as they are marketed as more sustainable material options in the product design industry.
This table organizes information for an Okala Life Cycle Assessment.
Life Cycle Assessment tools are useful for calculating environmental impacts of products, and include effects of energy use; air, water and land eutrophication; and human toxicity. The Okala LCA method is standardized for North American data.
In column 4, the cup with the lowest calculated impact, or most sustainability, is noted as the cup made from High Density Polyethylene derived from petroleum. The High Density Polyethylene cup derived from sugar has a marginally higher impact, indicated in column 5.
The word pairs used in this study target qualitative strategies of sustainable design.
These word pairs have been used to determine feelings of sustainability in previous Kansei studies presented in 2012, 2013 and 2014.
Let’s look at the experimental results from the participants.
The averaged results of the Kansei rankings are shown in this bar chart.
To produce these results, 276 people participated in the ranking exercise.
Each participant was given a set of the 6 cups and a rating questionnaire with the word pairs bracketing the 1 through 7 scale, shown on the y-axis. Participants were instructed to indicate where on the scale each cup fell for each of the word-pairs. The material and derivation of the material of each cup was written on the questionnaire with the ranking scales. For example, this cup was labelled “High Density Polyethylene derived from sugar” on the questionnaire.
There are two generalities apparent on this bar chart.
First, the polymer cups were strongly perceived to be Durable (compared to Delicate). The ”Durable” bar on the chart is dark blue.
The second generality addresses the original hypothesis, that disclosing the derivation of the polymers that make the cups will affect perceptions of natural-ness and overall sustainability of the cup products. The cups made with polymers derived from plants are grouped on the right side of the chart. The shorter bars indicate that they are perceived as more sustainable than the cups made with polymers derived from petroleum.
Let’s look at one specific example.
The most direct comparison of cups based on a difference in material derivation is the 2 High Density Polyethylene cups.
This bar chart shows the average rankings for the 2 High Density Polyethylene cups.
In 5 of the 6 rankings: Degradable, Natural, Raw, Harmless and Recyclable, the sugar-derived HDPE cup is perceived as more sustainable than the petroleum-derived HDPE cup. These differences are statistically significant.
This fits with the hypothesis that knowing plant-based polymer derivations creates a more sustainable perception of a polymer product.
The sixth ranking, for Durable, shows the petroleum-based HDPE cup to be perceived as more durable than the sugar-derived HDPE cup.
This difference is not statistically significant, however, suggesting that the specification or selection of a sugar-derived HDPE material would not reduce a product’s strong perception of durability.
This box plot of the rankings of the 2 High Density Polyethylene cups shows that the ranking responses included nearly every possibility, 1 through 7, for each word pair.
The high number of participants may have allowed for statistically significant results despite this variability.
I see the Natural ranking as the most notable here, not only because it is a statistically significant difference, but because HDPE’s degrade the same, and the Harmless-Toxic word pair has been shown in previous studies to not affect the overall perception of a product’s sustainability.
This result supports the hypothesis that informing people about the derivation of plant-based polymers creates stronger perceptions of the natural-ness of polymer products.
Looking back at the table of Okala Life Cycle Assessment details reminds us that the 2 HDPE cups are very similar in weight and overall impact.
Not only are they similar in weight and overall impact, but the sugar-derived HDPE cup and the petroleum-derived HDPE cup look the same, feel the same, smell the same, and they sound the same when tapped on a table.
The senses to don’t provide enough information to influence the recorded rankings.
Knowledge about the material derivation of the polymer must be the source of the differences in rankings.
Therefore, describing the product’s material as sugar-derived strengthens the perception of natural-ness of the product and the overall sustainability of the product.
There are two additional discussion areas included in the paper.
The first is discussion about unique characteristics of the Cellulose/Polypropylene composite cup, which has the lowest, or most sustainably-oriented rankings in 5 of the 6 word pairs.
There is other product research in color and visual texture that this finding supports. People consider warmer-toned products and visually textured products to be more sustainable.
The second is discussion about Durability, as the Polyethersulfone and Polylactic acid cups are perceived as the most durable. They also happen to the be the heaviest of the six samples.
The PES and PLA cups are the heaviest of the samples.
There is other product research in color and visual texture that this finding supports. People consider warmer-toned products and visually textured products to be more sustainable.
Durability may be associated with weight.
Approximately 2X and 4x heavier than the Cellulose/PP
Because it supports the original hypothesis, the most satisfying conclusion from this study is that disclosing plant-based polymer derivations does indeed create stronger perceptions of the natural-ness of polymer products and the overall sustainability of polymer products.
Thank you very much for your attention to this presentation, titled: Material Derivation Affects the Perception of Sustainability in Polymer Products.
I look forward to discussing this research with you any time.