Spiga Nord > Polyglycerols for the bioplastics industry
Technical polyglycerols and polyol formulations based on glycerine and polyglycerols support the development of bioplastics and starch-based compounds. Manufacturers can also use them to produce thermoplastic starch materials, commonly known as Thermoplastic Starch (TPS).
Starch is a renewable and widely available raw material. However, its crystalline structure prevents direct processing as a conventional thermoplastic polymer. To produce starch-based bioplastics, manufacturers combine starch with water, heat, mechanical energy and plasticisers. This process gelatinises the starch and increases molecular mobility. Polyols interact with its hydroxyl groups and modify the forces between the polymer chains. These changes allow processors to use conventional polymer-processing technologies.
Scientific research on starch-based systems identifies glycerine, diglycerol and polyglycerols as suitable plasticisers for TPS formulations. Their molecular weight, viscosity and hydrogen-bonding capacity influence the gelatinisation process. Their affinity for water and oligomer distribution also affect processing behaviour and final material performance.
Spiga Nord offers Refined Technical Polyglycerine and customised formulations. The company combines different polyglycerols, glycerine and, when required, water. This approach creates polyol systems tailored to the selected matrix, extrusion conditions and final product requirements.
From oligomer distribution to compound performance: Spiga Nord develops polyol systems for the specific requirements of bioplastic formulations.
Starch has a crystalline structure. This structure prevents manufacturers from processing it like a conventional thermoplastic material. To produce thermoplastic starch (TPS), manufacturers combine starch with water, a plasticiser and heat. Extrusion typically provides the required mechanical shear.
Under these conditions, glycerine and polyglycerols interact with the hydroxyl groups in the starch. They weaken the forces between the polymer chains and increase their mobility. These interactions progressively disrupt the crystalline structure. The resulting material can then enter conventional polymer-processing systems.
The proportions of water, glycerine and polyglycerols influence the behaviour of the formulation. Oligomer distribution, viscosity and processing conditions also affect the final result. Spiga Nord develops customised polyol formulations according to the characteristics of the matrix, the production equipment and the required material performance.
Bioplastic development requires a careful balance. Manufacturers must consider the origin of the raw materials, industrial processability and final material performance. They must also ensure adequate stability throughout production and use.
Starch-based systems present a specific challenge. Starch is naturally rigid and sensitive to moisture. Manufacturers must transform it into a homogeneous and processable thermoplastic phase. The plasticiser must support starch gelatinisation during processing. It must also perform consistently at the selected temperatures, residence times and shear forces.
Manufacturers widely use glycerine as a plasticiser for thermoplastic starch (TPS). It offers good effectiveness and broad availability. However, its low molecular weight can limit certain formulations. Some applications require greater stability at processing temperatures, lower moisture sensitivity or different interactions within the polymer matrix.
In specific experimental formulations, researchers observed that polyglycerol-plasticised TPS absorbed less moisture and offered greater thermal stability than TPS containing only glycerine. The same studies found good compatibility between polyglycerol and starch. They also recorded broadly comparable mechanical properties in the analysed TPS and polyethylene blends.
These results depend on the formulation, the type of polyglycerol and the processing conditions. Formulators should therefore evaluate each application individually rather than generalise the findings to every TPS system.
The main challenge involves selecting the most suitable combination of:
The composition of the plasticiser system gives manufacturers a practical way to control TPS behaviour during compounding. It also helps them adjust the properties of the final material.
Refined Technical Polyglycerine offers a broad and controlled oligomeric distribution.
The combination of residual glycerine, diglycerol, triglycerol and higher oligomers creates a functional polyol for industrial formulations and thermoplastic starch-based systems.
Formulators can use Refined Technical Polyglycerine as a plasticising component in compounds containing TPS. Its higher-molecular-weight oligomeric fractions may behave differently from glycerine alone. Customers should evaluate its performance according to the selected matrix, dosage and processing conditions.
The product offers controlled water content and a well-defined distribution of the main oligomeric fractions. These characteristics provide a consistent foundation for formulation development. Spiga Nord produces Refined Technical Polyglycerine from GMO-free vegetable glycerine and offers it with Kosher and Halal certifications.
Every starch-based formulation has different requirements. That is why Spiga Nord can develop customised polyol formulations by adjusting the composition to meet the customer’s technical objectives.
The preparations may include:
The ability to adjust the ratio of glycerine, diglycerol, and higher oligomers makes it possible to modify the average molecular weight and the profile of the plasticising system. Water can also be incorporated in controlled amounts when it serves as a functional parameter for the starch gelatinisation process.
A diluted preparation should therefore not be considered simply as a less concentrated version. In TPS systems, water plays a direct role in the gelatinisation process, influences the initial viscosity of the mixture, and promotes the penetration of the plasticiser into the starch granules. The most appropriate amount must be determined by considering the overall formulation and compounding conditions.
The specifications for custom formulations are agreed upon with the customer based on technically relevant parameters, such as oligomeric composition, glycerine content, water content, colour, and processing characteristics.
Choosing Spiga Nord means partnering with a manufacturer that specialises in the chemistry of glycerine and polyglycerols, capable of offering both standardised technical products and the ability to develop customised formulations.
Knowledge of the entire oligomer range makes it possible to adjust the polyol system composition by combining glycerine, diglycerol, and higher-chain polyglycerols according to customer needs. This represents a tangible advantage in the development of bioplastics, where raw material composition and process conditions are closely linked.
Spiga Nord can assist customers in defining the key parameters of the formulation, including oligomeric distribution, the ratio of glycerine to polyglycerols, and any water dilution.
Our approach is not to propose a one-size-fits-all solution, but rather to provide a flexible polyol platform that can be evaluated and optimised in collaboration with the compound manufacturer.
For Spiga Nord, every project in the bioplastics sector begins with an analysis of the matrix, the process, and the desired outcome. The goal is to transform the oligomeric distribution of polyglycerol into a formulative tool for the development of more advanced materials.
Our Products
Refined Technical Polyglycerine by Spiga Nord is a high-purity, multi-functional ingredient derived from vegetable glycerine.
It offers excellent lubricating, dispersing, and stabilizing properties, making it suitable for a wide range of industrial and technical applications.
Reliable and efficient, as PG-Ester or by itself, it supports improved process performance, product consistency, and formulation stability.