Global pressure-sensitive adhesives (PSAs) market was estimated at $9.9 billion in 2020 and projected to reach above $13 billion in 2026 growing at around 6% per year. The packaging industry accounts for the largest segment of PSAs market ($2 billion in 2018). During coronavirus outbreak, there is an increasing demand for PSAs in packaging and medical applications (labels, tapes, protective films etc.) triggered by the fact that population worldwide primarily buying fast moving consumer goods and food.
PSAs ensure adhesion upon light pressure and can be easily completely removed from the substrate by light pulling force. There is a need for biobased PSAs, especially in medical industry, most current candidates are non-biodegradable and can cause allergies.
Main goal of this project is to develop biodegradable PSAs based on polymers from soy derivatives, high oleic soybean oil- and soybean oil-based vinyl monomers (HOSBM and SBM, developed at NDSU) for applications in food packaging and/or medical industries.
Specific aims include synthesis of SBM- and HOSBM-based polymers range, formulation of PSAs thereof, evaluation of properties/performance of soy-based PSAs (including biodegradability). Presence of soy-based fragments in PSAs will provide the needed balance of viscous and elastic properties, thus, multiple bonding/debonding, required for these materials to function properly.
Identifying industrial partners to help with evaluating performance of the soy-based pressure-sensitive adhesives best candidates and show how well-suited new material is for applications in food packaging and/or medical industries is targeted.

The main goal of the proposed research is to develop biodegradable PSAs based on SBM- and HOSBM-derived ingredients. Chemical and structural versatility of SBM and HOSBM facilitate adhesion to a variety of substrates, while plasticizing (softening) ability of soy-based polymer fragments from SBM and/or HOSBM (in combination with other counterparts) ensures the needed balance of viscous and elastic properties, thus, multiple bonding and debonding required for PSAs best performance.
During one year, we (1 - Month 1-6) synthesize and characterize a range of soy-based acrylic polymers (latexes or solution polymers) and formulate PSAs thereof, (2 - Month 7-12) apply soy-based PSAs to various substrates for evaluation of their performance (tack, peel, shear), (3 - Month 10-12) select PSA samples with a desirable adhesive performance for biodegradability testing.
Identifying industrial partners to evaluate performance of the soy-based PSA best candidates to show how well-suited the new material for targeted applications is planned as well.

1. Range of PSAs formulations from newly synthesized polymers based on SBM and HOSBM.
2. Characterization/testing of the developed PSA formulations to determine feasibility to be applied in food packaging and/or medical applications.
Longer term goal is to provide soy-based biodegradable PSAs and test them at industrial partner facilities to evaluate perspectives of this new product commercialization.

Update:

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Update:

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Research Conducted
Pressure-sensitive adhesives (PSAs) are tacky materials at ambient conditions, can be easily attached to many surfaces with a light manually applied pressure. Many industries, such as packaging (labels, stickers, tapes), medical (band aids), electrical (joints in devices), automotive (attachment of car parts without bolts and welding) experience increased demand in this type of materials. Most raw resources used to get end-products are petroleum-based, non-sustainable, may cause allergic reactions after the contact with food or human skin. Natural raw materials are spectacular in terms of sustainability, nontoxic for human health. Sources such as plant oils (including soybean oil and high oleic soybean oil), plant proteins (including soy protein) are safe and even edible.
Our objective is to replace conventional petroleum-derived raw materials with soy-based alternatives in PSAs while keeping the targeted properties of end-products at high level. It is usually desired to create a bond between two dissimilar materials, that is why we test soy-based PSAs on glass, steel and polymer substrate. We have evaluated tack or how sticky soy-based PSAs are and strength of bonding they create.

Why the Research Important to North Dakota Soybean Farmers
Soybeans have up to 20% of the oil in their content, which is mostly used in the food industry, but also for biofuel production. Another potential application is the processing into polymeric materials for various applications such as packaging, films, adhesives, coatings etc. In current research we employ an environmentally friendly aqueous-based process to obtain polymers for making soy-based polymeric PSAs. Besides, we utilize the reaction, which allows to decrease process temperature down to room temperature, while maintaining high yield of final product (about 90%). Currently, up to 40% of targeted product consists of the soy-based ingredients.

Findings of the Research
The results show that PSAs obtained at room temperature with up to 40% replacement of petroleum-based ingredients with soy-based counterparts show properties and performance similar or better in comparison to commercial products (developed materials are compared to 3M products).

Benefits/Recommendations for North Dakota Soybean Farmers and the Industry
For the North Dakota soybean industry, this technology may become a prospective solution to applying crops for high value and high profit PSAs. Using soybean oil and high oleic soybean oil for making new soy-based PSAs offers sustainable and efficient alternative to the materials presented at the market, thereby adds value to the crop, makes it more profitable for farmers.

This proposal aims to provide the feasibility of using crops produced in the state of North Dakota for high value and high profit polymer materials for adhesives industry. Using soybean oil and high oleic soybean oil for making new materials has the ability to add more value to the crop, thereby make it more profitable for farmers. Thus, ability to produce soy-based biodegradable PSAs from soy oils from crop grown in state of North Dakota certainly strengthens the developed technology. Obtained results are expected to benefit North Dakota soybean farmers because the findings will diversify soy-based products with increased demand for soy oils. The market will get soy-based biodegradable PSAs for food packaging and/or medical applications. It will also help the state of North Dakota economy to involve investors and other soy processing industries.