PCM-Containing Viscoelastic Foams

Patent Title: VISCOELASTIC POLYURETHANE FOAM WITH COATING

Number/Link: WO2017/210439

Applicant/Assignee: Dow

Publication date: 7 December 2017

“Gist”: Open-celled visco-foam is impregnated with an aqueous dispersant composition containing a phase change material

Why it is interesting: According to Dow, open-celled viscoelastic polyurethane foams can be prepared by using a acid-modified polyolefin latex cellopener, as discussed before in this blog. In the current invention these open-celled foams are impregnated with an aqueous composition comprising an ionomer (a sodium salt of a maleic anhydride copolymer) and a microencapsulated PCM. The composition is said to ‘coat’ the cell struts with PCM and increase the comfort properties of the foam.
I wonder if with this process enough PCM can be in introduced to have a noticeable effect.

bluewave

Dow’s proprietary BLUEWAVE dispersion process is used to prepare the cellopening latex

Solid-Solid PU PCM

Patent Title: PHASE-CHANGE MATERIAL FOR STORING THERMAL ENERGY, MANUFACTURING METHOD AND USES OF SUCH A MATERIAL

 Number/Link:  WO2017/198933 (French)

Applicant/Assignee:  UNIV CERGY-PONTOIS

Publication date: 23 november 2017

Gist”: A crosslinked PEG-HMDI elastomer can be used as phase change material.

Why it is interesting: Phase change materials, used to dampen temperature cycles in buildings, are well known. Most organic phase change materials (e.g. paraffines) show solid-liquid phase transitions and therefore need to be macro- or micro-encapsulated. This invention is about polyurethane PCMs with a solid to solid phase transition, and therefore need not be encapsulated. The PU PCM is prepared by reacting a polyethylene glycol with a diisocyanate like HMDI together with a crosslinker like glycerol. The solid elastomer is then ground into powder which can be used in construction materials like plaster or cement. The transition temperature and the latent heat of the PCM is controlled through the mole weight of the PEG (e.g. 1000 to 2000 Da) and the degree of crosslinking.
Solid-solid PU PCMs are not new, see WO2011/089061 (Huntsman), which (in my opinion) presents a more elegant and flexible solution to the problem.

Phase_Change_Materials

Temperature damping by PCM (Wikimedia Commons)

 

Sequence-Defined Polyurethanes for Information Storage

Patent Title: UNIFORM SEQUENCE-DEFINED POLYURETHANES AND USES THEREOF AS MOLECULAR LABELS

 Number/Link: WO2017/194694

Applicant/Assignee:  Centre National de la Recherche

Publication date: 16 November 2017

Gist”: Stepwise immobilized polymer synthesis is used to make polyurethane having a predefined sequence of monomers

Why it is interesting: The invention is about monodisperse polyurethanes consisting of a well-defined sequence of monomers having various chain lengths and side groups – not unlike proteins or nucleic acids. In a first step a solid support (e.g. polystyrene beads) which bears a cleavable tether molecule is reacted with N,N’-disuccinimidylcarbonate and in a second step with an aminoalcohol like 5-amino-1-pentanol. Steps 1 and 2 are then repeated using the same or a different aminoalcohol. Finally the tether is cleaved from the support.  If 2 different aminoalcohols are used, a binary code can be encoded in the molecule which can later be read using a sequencing technique. The polyurethanes are said to be useful in anti-counterfeiting technologies.

Capture1

Reaction sequence according to the invention

Aliphatic Polyisocyanurate Composites

Patent Title: METHOD FOR PRODUCING A POLYISOCYANURATE COMPOSITE MATERIAL

 Number/Link: WO 2017/191216  (German)

Applicant/Assignee:  Covestro

Publication date: 9 November 2017

Gist”: Partially trimerized aliphatic diisocyanates are mixed with glass fiber and reacted using a trimerization catalyst

Why it is interesting: Conventional fiber-reinforced composites based on unsaturated polyesters, epoxies, polyurethane and the like are not weather-stable and need to be coated for outdoor use. Weather stable polyisocyanurate composites are known (WO2007/096216 – Huntsman) but are based on aromatic diisocyanates and show high reactivity and short ‘pot life’. According to this invention, PIR composites with improved reaction profile and weatherability can be prepared from partially trimerized aliphatic diisocyanates with a diisocyanate monomer content of less than 20% (w/w). In the examples commercially available HDI and IPDI trimer is used together with short glass fiber and a potassium acetate/PEG 400 blend as catalyst cured at a temperature of 160 to 180°C.

Isophorone diisocyanate (IPDI)

 

Modified Polyisocyanurates

Patent Title: MODIFIED POLYISOCYANURA TE PLASTIC AND METHOD FOR PRODUCTION THEREOF

 Number/Link: WO2017/182108 WO2017/182109  WO2017/182110  (German)  

Applicant/Assignee:  Covestro

Publication date: 26-october-2017

Gist”: Partially trimerized diisocyanates are modified with monofunctional isocyanate-reactive compounds before complete trimerization

Why it is interesting: This series of applications relates to transparent polyisocyanurate coatings with controlled hydrophilicty, hydrophobicity, high scratch resitance etc. According to the invention trimers of diisocanates are reacted with a sub-stoichiometric amount of monofunctional hydrophobic, hydrophilic or siloxane-containing compounds, and then completely trimerized. In the examples HDI-trimer (prepared by partially trimerzing HDI and removing the rest of the monomer by thin film distillation) is reacted with e.g. methoxyPEG 500, dodecanol, perfluoroheptanol and N-(3-trimethoxyxilylpropyl)foramide and then trimerized using potassium acetate as catalyst.  The materials can e.g. be used as anti-fog coatings on optical lenses or anti-fingerprint coatings on cell phones.

HDI-isocyanurate