Phosgene-Free Polyisocyanate with PDMS Backbone

Patent Title: MULTI-FUNCTIONAL CARBAMATE HAVING SOFT-SEGMENTS, POLYISOCYANATE OBTAINED VIA SUBSEQUENT NON-PHOSGENE SYNTHESIS METHODS, URETHANE PREPOLYMER AND ELASTOMERIC URETHANE HAVING SOFT-SEGMENTS DERIVED THEREFROM, AND PREPARATION METHOD THEREOF

 Number/Link: US20180186918

Applicant/Assignee:  Great Eastern Resins Industrial

Publication date: 5 July 2018

Gist”: Biscarbamate with PDMS softblock backbone is heat-cracked into diisocyanates

Why it is interesting: The invention relates to isocyanate-capped “softblock” siloxanyl prepared without using phosgene and polyurethanes derived therefrom. The invention is accomplished by reacting relatively high MW polydimethylsiloxanediamines with diphenylcarbonate.  The resulting biscarbamate is heated under reduced pressure to produce the diisocyanate and to remove the phenol by-product.  The isocyanates can be reacted with polyols and/or chain extenders to produce highly hydrophobic polyurethanes with low surface tension and good chemical resistance.

biscarbamate

Biscarbamate with PDMS backbone

 

TPUs from Block Polyester Polyols

Patent Title: THERMOPLASTIC POLYURETHANE HAVING HIGH TEAR PROPAGATION STRENGTH  & PROCESS FOR PRODUCING TRANSPARENT HARD THERMOPLASTIC POLYURETHANES

 Number/Link: WO2018/115460  WO2018/115468

Applicant/Assignee:  BASF

Publication date: 28 June 2018

Gist”:  Polyester polyols containing a “hard block” of polyethyleneterephthalate are used in the preparation of TPU 

Why it is interesting: According to this invention thermoplastic polyurethanes with a high hardness at a relatively low hardblock level (<75%), or a high tear strength at relatively low Tg (<5°C) can be prepared from a polyester polyol that is a block copolymer containing 10-50% of an aromatic polyester block, the rest being aliphatic polyester. In the examples diols are prepared from PET together with adipic acid and BDO or DEG. The diols are reacted with MDI or HDI and a chain extender like BDO or HDO.

PET

Poly(ethyeleneterephthalate)

UV Resistant Viscoelastic Foams

Patent Title: POLYURETHANE PRODUCT WITH SULFUR-CONTAINING POLYOL

 Number/Link: WO2018/111806

Applicant/Assignee:  Dow

Publication date: 21 June 2018

Gist”: VE foams using S-containing polyether polyols

Why it is interesting: According to this invention sulfur containing polyols improve the UV resistance of polyurethane materials.  It is believed that sulfur acts as a UV absorber incorporated into the polymer, thereby reducing the need for additives such as antioxidants.  In the examples an S-containing polyether diol is prepared by reacting 2,2′-thiodiethanol with propyleneoxide up to an OH value of  188 mg KOH/g. The diol is then used in an amount of 5 to 15% on the total polyol blend to prepare low resilience flexible foams showing an improved UV resistance.

 

TDE

2,2′-thiodiethanol

 

Scorch-Proof Polyurethane Foams

Patent Title:  LOW EMISSIONS SCORCH INHIBITOR FOR POLYURETHANE FOAM

 Number/Link: WO2018/064521

Applicant/Assignee:  Vanderbilt Chemicals

Publication date: 5 April 2018

Gist”: A synergistic mixture of antioxidants prevents scorch

Why it is interesting: “Scorch” is a discolouration of the center of (especially low-density flexible) polyurethane slabstock foams as a consequence of excessive heat build-up during production. It is believed to be the result of free-radical reactions of foaming components and additives, like the dimerisation of BHT – a common antioxidant. According to this invention the combination of three to (optionally) 5 specific antioxidants show an unexpected synergy towards prevention of scorch. The inventive composition consists of 2,2,4-trimethyl-1,2-dihydroquinoline, a lactone (e.g. 3-alkyl- benzofurane-2-one), a phenolic compound (e.g. an alkylated monophenol) and optionally a tocopherol (a vitamine E-type phenolic compound) and a phosphite compound.  The composition is said to have the added advantage of showing low volatile chemical emissions.

quinoline

2,2,4-trimethyl-1,2-dihydroquinoline

PIR-Oxazolidone Foams from Natural Oils

Patent Title: METHOD FOR MANUFACTURING A POLYURETHANE-MODIFIED FOAM, FOAM OBTAINED, AND USES

Number/Link: US2018/0030196

Applicant/Assignee:  Soprema et al.

Publication date: 1 February 2018

Gist”: Unsaturated natural oils are epoxidized and reacted with an excess of isocyanate in the presence of a blowing agent.

Why it is interesting: Conventionally natural oils are incorporated into polyurethanes by first converting them to polyols (“NOPs”) by hydroformylation or epoxidation and ring opening and then reacting the NOPs with isocyanates. According to this invention the natural oils (preferably extracted from microalgae) are epoxidized and then mixed and heated with a (e.g. 3:1) excess of isocyanate (e.g. polymeric MDI) in the presence of a blowing agent (e.g. isopentane). It is said that oxazolidone rings from the isocyanate-epoxy reaction will form at the same time as isocyanurate rings and homopolymerized epoxides. The foams are said to be useful for thermal insulation applications.

oxazolidone

Formation of oxazolidone rings according to the invention