Introduction of phosphorus into the polyethyleneterephthalate molecule via disodium 1,2-dicarbomethoxyethylphosphonate–II. A study on the influence of the modifier on the properties of polyethyleneterephthalate

The effect of disodium 1,2-dicarbomethoxyethylphosphonate on the polycondensation stage is studied. It is found that the polycondensation stage proceeds normally at 1–9% (by weight) of the combined dimethylterephthalate and ethylene glycol weights. The phosphorus-containing polyethyleneterephthalate obtained showed improved resistance to combustion and better thermal stability.     

A STUDY ON THE TRANSESTERIFICATION REACTION OF DIMETHYL AND DIETHYL PHOSPHITE WITH 1,3-DICHLOROPROPANOL-2

Abstract

The transesterification process of dimethyl and diethyl phosphite with 1,3-dichloropropanol-2 is examined. It is found that the reaction proceeds in the absence of catalyst at a temperature of 155°, whereas in the presence of morpholine as a catalyst it takes place at 126°C. The transesterification of dimethyl phosphite and diethyl phosphite with 1,3-dichloropropanol-2 is accompanied by the evolution of dimethyl and diethyl ethers and alkyl halides (methyl chloride and ethyl chloride).     

Synthesis and Characterization of Novel Cycloalkanespiro-5-Hydantoin Phosphonic Acids

A series of new cycloalkanespiro-5-hydantoin phosphonic acids have been synthesized and characterized. The mixture of [(2,4-dioxo-1,3-diazaspiro-alkane-3-yl)-methyl]phosphonic acids and [(2,4-dioxo-1,3-diazaspiro-alkane-1,3-diyl)dimethyl]diphospho-nic acids was obtained from cycloalkanespiro-5-hydantoins, formaldehyde, and phosphorus trichloride in a molar ratio of 1:2:2, by a procedure modified by us. Their structures were proved by means of IR, ¹H, ¹³C{¹H} and ³¹P NMR spectroscopy.     

Chemical Degradation of Polymers (Polyurethanes,Polycarbonate and Polyamide) by Esters of H-phosphonic and Phosphoric Acids

A review of the research efforts on the development of pathways for the degradation of polymer–wastes of polyurethanes, polycarbonates and polyamides by esters of H-phosphonic and phosphoric acids is presented. Our group has made it clear, thanks to a vast research program devoted to this subject, that alkyl esters of H-phosphonic and phosphoric acids can be used as very effective degrading agents for polymers. Products and mechanism of polyurethanes degradation by treatment with phosphonates are reviewed in this work. The interest of phosphorus-containing degradation products lies on the fire retardant properties that these phosphorous moieties introduce in the recovered molecules. Most of these phosphorilated molecules can be easily reapplied as reactive intermediates by treatment with propylene oxide and used for the preparation of rigid polyurethane foams. The interaction of poly[2,2-bis(4-hydroxyphenyl)-propanecarbonate] (PC) with H-phosphonic acid dialkyl esters [(RO)₂P(O)H, where R = CH₃ or CH₂CH₃], or with triethyl phosphate (CH₃CH₂O)₃P(O) yielded interesting phosphorus-containing oligocarbonates. Polyamide-6 can be converted into functional reactive oligomers with new properties by treatment with diesters of the H-phosphonic acid.     

Novel routes to aminophosphonic acids: Interaction of dimethyl H‐phosphonate with hydroxyalkyl carbamates

It was found that the reaction of dimethyl H‐phosphonate ( 1 ) with 2‐hydroxyalkyl‐N‐2′‐hydroxyalkyl carbamates at 135°C includes several chemical reaction steps: (i) chemical transformations of 1‐methyl‐2‐hydroxyethyl‐N‐2′‐hydroxyethyl carbamate ( 2 ) and 2‐methyl‐2‐hydroxyethyl‐N‐2′‐hydroxyethyl carbamate ( 3 ); (ii) transesterification of dimethyl H‐phosphonate with 2 and 3 , and with secondary hydroxyl‐containing compounds that are formed during the course of the chemical transformation of 2‐hydroxyalkyl‐N‐2′‐hydroxyalkyl carbamates; (iii) hydrolysis of 1 and dialkyl H‐phosphonates, formed via transesterification of 1 with secondary hydroxyl‐containing compounds. The interaction was studied by means of ¹H, ¹³C, ³¹P NMR, and FAB mass spectroscopy. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:119–124, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20404     

Microwave‐Assisted Single‐Step Synthesis of Poly(alkylene hydrogen phosphonate)s by Transesterification of Dimethyl Hydrogen Phosphonate with Poly(ethylene glycol)

Summary: Poly(alkylene hydrogen phosphonate)s with a number‐average molecular weight of about 3 000 Da were obtained by a transesterification of dimethyl hydrogen phosphonate with poly(ethylene glycol) (PEG 400) under microwave irradiation with a very short reaction time (55 min) relative to that of classical thermal heating (9 h). The structure of the resulting polymer was confirmed by ¹H, ³¹P, and ¹³C NMR spectroscopy. The molecular weight was determined by ¹H, ³¹P{H} NMR spectroscopy, MALDI‐TOF, and GPC.

The transesterification of dimethyl hydrogen phosphonate with poly(ethylene glycol).     

Synthesis of poly(oxyethylene phosphonate)s bearing oxirane groups in the side chain

The interaction between poly(oxyethylene phosphonate)s and 1,2-epoxy-7-octene has been investigated. It has been established that in the presence of benzoyl peroxide there proceeds a selective addition of the P( )H group to the C()C double bond. Poly(oxyethylene phosphonate)s bearing oxirane groups in the side chain have been synthesized. The new polymers can be used as polymer carriers of drugs. © 1997 John Wiley & Sons, Inc.