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.



Flexible Foams Containing PPE Polyols


 Number/Link: WO2015/041905

Applicant/Assignee: SABIC

Publication date: 26-03-2015

Gist”: Use of poly(phenylene ether) polyols in flexbile foams

Why it is interesting: As expected Sabic continue their series on the use of poly(phenylene ether) in polyurethane materials. This application is about the use of (some) PPE polyol in flexible foams. The resulting foams are said to have improved hardness, tear- and tensile strength. In the examples 10 to 40% of a PPE diol (on total polyol) is used together with other polyols, MDI or TDI and water as blowing agent, resulting in flexible foams with densities ranging from about 25 to 50 kg/m³. The PPE diol is a copolymer of 2,6-dimethylphenol and 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane with an equivalent weight of about 1000.

PPE diol used in the invention. Q5 and Q6 pare methyl.

PPE diol used in the invention. Q5 and Q6 are methyl groups.

Polyurethane “Combination Foam”: a TPU/PU Composite


 Number/Link:  WO2014/023794   (German)

Applicant/Assignee: BASF

Publication date: 13-02-2014

Gist”: Foamed TPU particles are embedded in a foamed elastomer of the same chemical composition to improve mechanical properties.

Why it is interesting: Foamed, closed-cell TPU particles are incorporated in a foamed, open-cell PU matrix which has a higher density and is produced from essentially the same chemicals, resulting in perfect compatibility and adhesion between the two components.  In the examples 30-40 % (w/w) of expanded TPU particles with a bulk density (“Shüttdichte”) of 89 kg/m³ are incorporated in an elastomer with a density of 200-300 kg/m³. Size of the TPU particles is not given but the preferred size range is 1mm to 2 cm.

Expanded TPU particles by BASF

Expanded TPU particles by BASF