PU Elastomers with Extremely High Elongation

Patent Title:  Polyurethane Elastomer with High Ultimate Elongation

 Number/Link: US2018/0312623

Applicant/Assignee:  UNIV PENNSYLVANIA

Publication date: 1 November 2018

Gist”: Low hardblock polyurethane-polyurea elastomers are prepared from low unsat diols, HDI and a bulky diamine chain extender

Why it is interesting: The current invention relates to PU  elastomers which are said “to  have the highest reported elongation-at-break among known polyurethane elastomers“. The materials are prepared from an NCO-ended prepolymer consisting of a low unsaturated, low dispersity diol and a symmetric diisocyanate (i.e. no 4,4′-MDI), which is reacted with a “bulky” diamine chain extender. In the examples Acclaim 4200 (polyether diol with OHv 28) is used together with HDI and 2-methyl-1,5-pentanediamine. The elastomer showed an elongation at break of more than 2000%.
Because these materials have a low- and non-aromatic hardblock content, it is my opinion that they show creep rather than elasticity.



TPU Nanocomposite


 Number/Link: WO2018/185650 (Spanish)


Publication date: 11 October 2018

Gist”: Protein-stabilized nano- calciumcarbonate particles are incorporated into a thermoplastic polyurethane composition

Why it is interesting: Calciumcarbonate nanoparticles are prepared by mixing a solution of sodium carbonate, sodium caseinate and calciumchloride in a high pressure homogenizer. Particles are formed of CaCO3 embedded in a protein matrix that stabilizes that particles against aggregation. Particle size is (pref) 150-300nm with primary CaCO3 particles of 5-10nm. The particles are used in an amount of (pref) 0.6-1% (w/w) on a TPU composition. The TPUs are said to show increased mechanical properties and improved cell growth and are said to be useful for biomedical applications.


Stabilized nanoparticles (Wikipedia)

PU Elastomers from SGO Polymerized Acrylic Polyols


 Number/Link: WO2018/132648

Applicant/Assignee:  BASF

Publication date: 19 July 2018

Gist”: Solvent-free acrylate polyols are reacted together with polyether polyols and diisocyanates

Why it is interesting: In this invention a solvent-free (“100% solids” in the patent’s terminology) acrylic polyol is blended with a conventional polyether polyol and reacted with an aliphatic or aromatic diisocyanate.  The acrylic polyol is prepared by co-polymerizing (e.g.)  ethyl- or butyl (meth)acrylates, styrene and a hydroxyl functional acrylate like 2-hydroxyethyl acrylate or 4-hydroxybutyl acrylate, using BASF’s “solid grade oligomer” (SGO) polymerization process. The SGO process is a high temperature and high pressure continuous process allowing for the production of low-solvent acrylic resins. The polyurethanes are said to have increased physical properties, esp. tear- and tensile strength properties.