The new issue 4/2019 of PU Magazine International has been published!
In this new issue you can read about the European flexible PU foam market development, past fairs and conferences such as Europur & Euro-Moulders Conference in Lisbon, Portugal, and the interzum in Cologne, Germany. We also cover the upcoming CPI in Orlando, Florida and the report on K 2019 with its leitmotif Circular Economy.
Featured technical articles are:
- Dry demoulding – cost-effective PU components through permanent release coatings
(C. Hopmann, P. Surray, D. Schneider, K. Vissing, M. Noeske, P. Bitomsky, IKV and IFAM)
In an IGF cooperation project at the Institute for Plastics Processing (IKV), Aachen, and the Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM), Bremen, a permanent release coating was investigated as an alternative to conventional release agents in polyurethane (PU) processing. Central aspects are the influence of catalysis in the PU formulations on the demoulding behaviour and the transfer of the technology to industrial standards. Casting experiments and near-surface analysis were used to determine a catalyst class compatible with the release coating. New requirements for process control and mould design were defined for the industrial application of the technology and implemented in an innovative mould concept.
- The evolution of custom-made high-pressure mixing heads for the most demanding polyurethane manufacturing applications
(A. Bartolini, G. Molteni, Cannon)
Polyurethane dosing equipment manufacturers face more and more stringent requirements in the contemporary marketplace due to the rapid development of the chemistry and increasingly sophisticated requisites by manufacturers and their suppliers. High flexibility in industrial production is pushing the technology of mixing and dosing towards levels of technical excellence never reached before. The purpose of this paper is to share with the industrial technical community the latest achievements in high-pressure polyurethane mixing from the Cannon Group’s point of view.
- Advances in the use of bio-based components in aqueous polyurethane dispersions for coating and adhesive applications
(S. Hurff, M. Shen, A. Sendijarevic, I. Sendijarevic, DuPont Tate & Lyle and Troy Polymers)
The use of solvent-free waterborne urethane dispersions (PUDs) is widely discussed in literature and growing across various industries due to environmental factors. The introduction of 1,3-propanediol (1,3-PDO) as a bio-based component of chain diols is accepted as shown by its use on commercial scale to produce polyester and polyether polyols. Solvent-free bio-based systems must offer all the same required properties of current commercial products with the added advantage of being eco-friendly and sustainably sourced. To obtain PUDs with good performance, the effects of varying the block components must be understood. The introduction of dimethyol propanoic acid (DMPA) pendant ionic groups into hard segment blocks facilitates the formation of stable PUDs of acceptable solids loading by increasing hydrogen bond interactions. The use of lower molecular weight bio-based polyester/polyether soft segments based on 1,3-PDO with increased hard segment blocks builds on our understanding of the structural relationships and properties in coatings and adhesives applications. The bio-based films prepared in this investigation provide an extended useful thermal range compared to reference commercial petroleum based PUDs as well as equivalent toughness and flexibility for these one-component waterborne polyurethanes.
- A comparison of properties enabled by various plasticizers in MDI/polyether and MDI/polyester-based TPUs
Certain thermoplastic polyurethane (TPU) applications demand the addition of plasticizer to lower the hardness sufficiently. However, the choice of plasticizer can completely change the final properties of the TPU. A study was completed to compare these properties. Various plasticizers were tested in a typical MDI/polyether TPU system and a typical MDI/polyester TPU system. Standard physical property testing was completed for these TPU systems as well as dynamic mechanical analysis (DMA). The relationships between the rudimentary properties of the DMA (storage modulus, loss modulus, tan d) and the measured physical properties were compared. As a result, a rationale for plasticizer selection in TPUs, as well as an appreciation for some of the fundamental physics behind those choices, can be understood.
Further information about the new issue at https://www.gupta-verlag.com/magazines/pu-magazine-international/04-2019.