Production of biopolymers and biobased polymers

Plastics: fossil or biobased? Both!

Synthetic or petroleum-based polymers offer significant advantages that have benefited mankind for more than a century. It is therefore hardly surprising that more than 90 percent of the polymers produced worldwide are based on crude oil. However, in addition to the advantages they offer, their disadvantages are now becoming increasingly apparent, including the depletion of fossil resources, pollution of the world's oceans and increased CO2 emissions caused by the combustion of non-degradable plastics.

New approaches therefore aim to significantly increase recyclability, for example through the increased use of monomaterials. Despite these efforts, however, alternative and complementary approaches are also required to meet the aforementioned challenges. This circumstance, as well as climate change and increased environmental awareness, has directed the focus towards plastics made from biogenic raw materials. Biobased plastics are mostly biodegradable, biocompatible and can be produced CO2-neutrally.

Biodegradable polymers are in particular high demand when plastics are required for direct use in the environment, for example in agricultural films. These simply decompose over time and leave no traces of microplastics. The aspect of biocompatibility plays a part especially in medical and cosmetic applications.

At Fraunhofer IGB, we contribute significantly to the development of novel biobased plastics by designing and optimizing processes for the production or purification of various biobased polymers and biopolymers.

Our offer: process development for biopolymers and biobased polymers from raw and residual material streams

Native biopolymers (lignin, cellulose, hemicellulose, latex, inulin or chitin) are obtained at the IGB after purification and extraction from renewable raw materials or waste streams.

Another option is using these material flows after appropriate conversion:

  • Microbially produced polymers, e.g. polyhydroxyalkanoates (PHA)
    We use waste streams such as used cooking oils, lignocellulose fractions or volatile fatty acids from wastewater treatment for the production of various PHAs.
  • Biobased monomers (hydroxycarboxylic acids and dicarboxylic acids)
    We produce biobased monomers biotechnologically by fermentation from waste streams. These can subsequently be chemically polymerized into polymers (polyesters, polyamides, polyurethanes) with the desired properties. Our portfolio includes malic acid, itaconic acid, xylonic acid, long-chain dicarboxylic acids (lc-DCA) and lactic acid. 

Based on underlying thermodynamic-mechanical data, biopolymers can replace fossil-based polymers or even open up new fields of application. 

We will gladly investigate the processing of native biopolymers and the microbial production of PHA, hydroxycarboxylic acids and dicarboxylic acids as well as the purification of polymers based on your individual waste streams.

Native Biopolymers

Chitin – after cellulose – is the second most common natural polymer on earth and is formed as a structural component by fungi, insects and crabs. Cellulose is the main component of plant cell walls. Lignocellulose is the structural material in the cell wall of all woody plants and the main component of residues such as straw or wood.

After purification and extraction, we obtain native biopolymers such as lignin, cellulose, hemicellulose, chitin, latex or inulin from renewable raw materials or waste streams at Fraunhofer IGB. For instance, we purify residual materials containing chitin (insect skins, waste from fishing and mushroom cultivation) to extract the chitin and subsequently convert it into chitosan.

We also fractionate lignocellulosic biomass from agricultural and forestry waste streams into the fractions cellulose, hemicellulose and lignin. Due to our expertise in the enzymatic hydrolysis of the individual polymers, we are able to open them up for further applications.

We have also been working on the extraction of latex and inulin from Russian dandelions.

Die Häute der Larven enthalten Chitin, das in InBiRa extrahiert und in wertvolles Chitosan umgewandelt wird.
© Fraunhofer IGB
The skin of insect larvae contains chitin, which is extracted at the IGB and converted into valuable chitosan.
chitosan
© Fraunhofer IGB
Chitosan, purified from insect skins.
chitosan film
© Fraunhofer IGB
Chitosan is able to form films, which is important for its use as sizing agent.

Further Information

Processing of chitin from crab shells and insect skeletons

Pulping of lignocellulose

Latex and inulin from dandelion roots

Microbially produced biopolymers

Polyhydroxybutyrate-co-hydroxyvalerate Copolymer (PHBV)
© Fraunhofer IGB
Polyhydroxybutyrate-co-hydroxyvalerate copolymers (PHBV)

Polyhydroxyalkanoates (PHA) – biodegradable and biocompatible

 

Polyhydroxyalkanoates (PHA) are bacterial storage polymers whose production is induced by nutrient limitation and excess carbon. The best-known representative of PHA is polyhydroxybutyrate (PHB) and its copolymers – above all PHBV (polyhydroxybutyrate-co-hydroxyvalerate) – are of major importance for the production of bioplastics.

The microbial synthesis of PHA offers the advantage of producing biopolymers with the desired thermal and mechanical properties (e.g. glass transition and melting temperature) by selecting the microorganisms and substrates and by optimizing the bioprocess itself.

Regardless of their composition, PHAs are characterized by biocompatibility and biodegradability. This means that they can be used in packaging, e.g. as disposable plastic bottles for non-food applications, for medical implants and agricultural films to replace various fossil-based polymers (e.g. polyethylene).

In our process optimization, the microorganism is able to accumulate more than 90 percent PHA in the cell. A purification process is therefore potentially no longer necessary but is already established for the production of high-purity PHA.

We produce different variants of PHA and copolymers of PHBV with varying valerate content according to the requirements for various applications. For this, we use waste cooking oil, volatile fatty acids (from wastewater treatment), crude glycerine and other suitable waste  

Biobased hydroxy and dicarboxylic acids as monomer building blocks for bioplastics

At Fraunhofer IGB, we produce hydroxycarboxylic acids and dicarboxylic acids from biogenic waste streams using various fermentative processes. Our portfolio includes malic acid, itaconic acid, xylonic acid, long-chain dicarboxylic acids (lc-DCA) and lactic acid, which can be polymerized in downstream processes.

When using biobased carboxylic acids, the desired polymer properties can be achieved not only via the monomer itself, but also via the polymerization conditions

Although the process development, taking into account the substrate, its feed or the microorganism, has no influence on the properties of the target molecule, it is nevertheless crucial for product concentration and conversion efficiency. In the case of xylonic acid, we were able to achieve titres of over 300 g/L.

Homopolymer malic acid
© Fraunhofer IGB
Homopolymer malic acid
Copolymers of polyol and malic acid in a ratio of 1:15
© Fraunhofer IGB
Copolymers of polyol and malic acid in a ratio of 1:15

Polymalate – as a laminating adhesive?

 

Polymalates are polymers of the dicarboxylic acid malic acid. The consortium of the Malum project is concerned with the fermentative production of enantiomerically pure malic acid, further purification and the subsequent production of polymers. While the IGB is involved in the scale-up of fermentation and downstream processing in this project, one of our project partners, HPX Polymers GmbH, is responsible for the polymerization of L-malic acid.

Homopolymers of racemic malic acid are water-soluble, biocompatible and biodegradable, but too hard and brittle for the intended applications.

Initial tests were carried out with commercially available DL-malic acid. In the project, novel biopolymers with higher elasticity and durability were produced by functionalization or copolymerization with other monomers. Initial application tests have shown that these polymers can be used as laminating adhesives.

Further Information

Long-chain dicarboxylic acids from plant oils

Fermentative production of hydroxy and dicarboxylic acids

Malic acid, itaconic acid, furandicarboxylic acid and xylonic acid – as monomers for biobased polymers

Range of services and collaboration

  • Qualitative and quantitative analysis of the chemical composition of the raw or waste stream (chitin, lignin, cellulose, hemicellulose, ash, fat, protein)
  • Fractionation / purification of various raw and waste streams
  • Screening for microbial polyhydroxyalkanoate producers
  • Qualitative and quantitative analysis of polyhydroxyalkanoates
  • Optimization of the fermentative production of hydroxy- and dicarboxylic acids
  • Development of purification strategies for biobased carboxylic acids and microbial polymers
  • The respective processes can be scaled up at our institute branch in Leuna, Fraunhofer CBP..
  • In-house post-modification of various polymers

We will gladly investigate the microbial production or purification of biobased polymers or biopolymers from your waste streams on your behalf.

Efficient processes thanks to methodological expertise

Our expertise in bioprocess optimization, scaling and analytics is used to counter the higher costs of biopolymers compared to petroleum-based polymers at initial stages of development in order to increase the respective yield and the economic efficiency of the developed process.

Depending on the starting material and the desired target product, we select the most suitable technology for fractionating and purifying the substrates from renewable raw materials and waste streams. The analytical methods required to characterize the starting material or to evaluate the process are already established at the IGB.

Publications

  • Hahn T, Alzate MO, Leonhardt S, Tamang P, Zibek S. Current trends in medium-chain-length polyhydroxyalkanoates: Microbial production, purification, and characterization. Eng Life Sci. 2024;e2300211. https://doi.org/10.1002/elsc.202300211
  • Hahn T, Egger J, Krake S, Dyballa M, Stegbauer L, von Seggern N, Bruheim I, Zibek S (2024) Comprehensive characterization and evaluation of the process chain and products from Euphausia superba exocuticles to chitosan. Journal of Applied Polymer Science, vol 141. doi:https://doi.org/10.1002/app.54789
  • Hahn T, Tafi E, von Seggern N, Falabella P, Salvia R, Thomä J, Febel E, Fijalkowska M, Schmitt E, Stegbauer L, Zibek S (2022) Purification of Chitin from Pupal Exuviae of the Black Soldier Fly. Waste and Biomass Valorization, vol 13. doi:10.1007/s12649-021-01645-1
  • Pravesh Tamang, Carmen Arndt, Johanna Bruns-Hellberg, & Regina Nogueira. (2021). Polyhydroxyalkanoates production from industrial wastewaters using a mixed culture enriched with Thauera sp.: Inhibitory effect of the wastewater matrix. Environmental Technology & Innovation, 21, 101328. https://doi.org/10.1016/j.eti.2020.101328
  • Pravesh Tamang & Regina Nogueira (2021). Valorisation of waste cooking oil using mixed culture into short- and medium-chain length polyhydroxyalkanoates: effect of concentration, temperature and ammonium. Journal of biotechnology, 342, 92-101.https://doi.org/10.1016/j.jbiotec.2021.10.006
  • Hahn T, Tafi E, Paul A, Salvia R, Falabella P, Zibek S (2020) Current state of chitin purification and chitosan production from insects. Journal of Chemical Technology & Biotechnology, vol 95. doi:10.1002/jctb.6533
  • Hahn T, Torkler S, van der Bolt R, Gammel N, Hesse M, Möller A, Preylowski B, Hubracht V, Patzsch K, Zibek S (2020) Determining different impact factors on the xylonic acid production using Gluconobacter oxydans DSM 2343. Process Biochemistry 94:172-179. doi:https://doi.org/10.1016/j.procbio.2020.04.011
  • Pravesh Tamang, Aniruddha Bhalerao, Carmen Arndt, Karl-Heinz Rosenwinkel & Regina Nogueira (2020). Ein integrierter Ansatz zur Biopolymerproduktion aus Abwasser. Wasser Abfall, 06, 19-22. https://doi.org/10.1007/s35152-020-0228-3
  • Pravesh Tamang, Rintu Banerjee, Stephan Köster, & Regina Nogueira (2019). Comparative study of polyhydroxyalkanoates production from acidified and anaerobically treated brewery wastewater using enriched mixed microbial culture. Journal of environmental sciences, 78, 137–146. https://doi.org/10.1016/j.jes.2018.09.001
  • Seibert-Ludwig D, Hahn T, Hirth T, Zibek S (2019) Selection and optimization of a suitable pretreatment method for miscanthus and poplar raw material. GCB Bioenergy, vol 11. doi:doi:10.1111/gcbb.12575
  • Dorsam S, Fesseler J, Gorte O, Hahn T, Zibek S, Syldatk C, Ochsenreither K (2017) Sustainable carbon sources for microbial organic acid production with filamentous fungi. Biotechnology for Biofuels, vol 10. doi:10.1186/s13068-017-0930-x
  • Werner, N., and S. Zibek (2017) Neue Biokatalysatoren zur Herstellung langkettiger Dicarbonsäuren. BIOspektrum. 23: 706-708.
  • Werner N, Zibek S (2017) Biotechnological production of bio-based long-chain dicarboxylic acids with oleogenious yeasts. World J Microbiol Biotechnol, vol 33, 2017/10/07 edn. doi:10.1007/s11274-017-2360-0
  • Kreuzberger M, Hahn T, Zibek S, Schiemann J, Thiele K (2016) Seasonal pattern of biomass and rubber and inulin of wild Russian dandelion (Taraxacum koksaghyz L. Rodin) under experimental field conditions. European Journal of Agronomy, vol 80. doi:http://dx.doi.org/10.1016/j.eja.2016.06.011
  • Hahn T, Klemm A, Ziesse P, Harms K, Wach W, Rupp S, Hirth T, Zibek S (2016) Optimization and Scale-up of Inulin Extraction from Taraxacum kok-saghyz roots. Natural Product Communications, vol 11.

Reference projects

October 2021 – October 2024

InBiRa

InBiRa – the insect biorefinery: From the utilization of organic residues and waste to the manufacture of products

In the InBiRa project, an insect biorefinery that converts waste and residual streams into new high-quality products is being built for the first time.
This is achieved using the insect larvae of the black soldier fly. The larvae consist of proteins, fats and chitin, from which new products can be manufactured.

October 2021 – October 2024

KoalAplan

Biorefinery Büsnau: Municipal wastewater as a source of ammonium nitrogen, hydrogen and bioplastics

At the University of Stuttgart's teaching and research wastewater treatment plant in Büsnau, three products are extracted from municipal wastewater: Ammonium, hydrogen and polyhydroxyalkanoates (PHA).

 

 

October 2021 – October 2024

BW2Pro – Biowaste to Products

The EU and the state of Baden-Württemberg are providing around 5.9 million euros in funding for the construction of a biowaste refinery on the site of the municipal biogas fermentation plant operated by Abfallwirtschaft Rems-Murr AöR (AWRM) in Backnang. In the future, one ton of biowaste per day will be processed here into products and raw materials such as fibers, flower pots, fertilizer and biogas.

January 2021 – December 2023

LaChiPur

Treatment of complex process wastewater with bifunctional biobased flocculant

The aim of the LaChipur project is to develop a biobased and functionalized flocculant for the efficient purification of seasonally occurring complex agro-industrial wastewater using residual materials from the food industry. The sustainable flocculant should be customizable to the respective load by varying the composition and thus show optimized efficiency.

May 2019 – April 2022

KEFIP

Complementary chemical-biotechnological process development for the novel production of 2,5-furandicarboxylic acid (FDCA) from inulin-accumulating plants

The objective of the KEFIP project is the development of a multi-stage process for the conversion of inulin-containing chicory root beet, which is produced as agricultural waste, to 2,5‑furandicarboxylic acid. Processes for inulin extraction, conversion to fructose and conversion to 5‑hydroxymethylfurfural as well as its oxidation to the platform chemical 2,5‑furandicarboxylic acid are investigated in order to provide the chemical industry with a raw material for polyester or polyamide production.

 

October 2017 – September 2020

SusPackaging

Sustainable production of polyhydroxyalkanoates (PHA) for packaging materials

Due to the growing awareness of environmental pollution caused by plastics, the demand for environmentally friendly packaging is increasing – especially in the cosmetics and food industry. The aim of the SusPackaging project is therefore to establish a green value chain for the production of bio‑based and biodegradable packaging materials. As part of the project, Fraunhofer IGB is investigating microbial polyhydroxyalkanoates (PHA), which have similar properties to conventional plastics but are biodegradable.

August 2017 – January 2021

Hydrofichi

Biobased hydrophobic and dirt-repellent finish for the substitution of pPerfluorochemicals (PFCs) on textile surfaces with chitosan derivatives

The aim of the Hydrofichi project is to modify textile surfaces using renewable raw materials in order to replace environmentally harmful and toxic agents that have been used up to now. For this purpose, a chitosan-based hydrophobic finishing of textiles is being developed.

 

March 2015 – February 2018

ChitoTex

Development and production of new insect chitosan and chitosan based functional coatings for yarns and textile fabrics

The aim of this project is the development of insect chitin as a sustainable chitin source for use as a functional surface coating of yarns and of technical textile surfaces. The project will consider the entire value creation chain: starting with the production of chitin from secondary streams of industrial insect cultivation, through a targeted enzymatic and chemical modification of chitin and chitosan, to the application in functional coating of textile surfaces and yarns.

January 2014 – December 2017

BIO-QED

Quod erat demonstrandum: Fermentative production and scale-up for the production of 1,4-butanediol and itaconic acid with the aim of cost reduction and improved sustainability  

The Industrial Biotechnology Group of Fraunhofer IGB is concerned with the selection of suitable second-generation raw materials and the production of sugars from these raw materials and the associated toxicity tests for microbiological utilization. WP2 is concerned with the establishment of fermentation for the production of BDO and IA from the selected raw materials. The working group will provide the project partners with advice on this.

 

July 2013 – December 2016

Lignoplast

Functionalized lignin cleavage products as synthesis building blocks for the production of adhesives, coatings, polyurethanes and epoxides

The aim of the Lignoplast project, led by the Fraunhofer Center for Chemical-Biotechnological Processes (CBP), is the development of adhesives, coatings, polyurethanes and epoxides based on chemically and enzymatically modified lignins.

January 2012 – December 2015

BioConSepT

From the plant to the plastic

The EU-funded BioConSepT project, which involves 30 European partners from research and industry in addition to the Fraunhofer IGB, is investigating the use of second-generation raw materials for the production of biobased polymers. The aim of the project is to provide processes that convert second-generation raw materials into valuable chemicals.

May 2010 – March 2014

Lignocellulose biorefinery

Digestion of lignocellulosic raw materials and complete material utilization of the components

The aim of this project, under the direction of DECHEMA, was to develop and establish a process for the complete material use of all components of lignocellulose by obtaining bio-based products based on cellulose, hemicellulose and lignin within a biorefinery.