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At least 901 records · Page 50Linked to original sources
PubMed2005

Size removal on polyester fabrics by plasma source ion implantation device.

Plasma treatment was evaluated as an alternative clean desizing technology in this work. As indicated by weight loss, O2 plasma treatment efficiently removed sizing agents such as polyvintyl alcohol (PVA), polyacrylic acid esters and their mixture (MIX) on polyethylene terephthalate (PET) fabrics. SEM pictures of the plasma treated samples directly proved the disappearance of the sizing agents. XPS analysis showed apparent changes in chemical composition and functional groups of the PET surface after O2 plasma treatment. Carbon content decreased due to the removal of sizing agents while oxygen content increased. O2 plasma treatment also increased hydrophilic functional groups of sizing agents, which is confirmed by C1s and O1s deconvolution analyses. After O2 plasma treatment, the PET fabric was subjected to conventional desizing process at different temperatures. Except for the PET fabric sized with PVA, plasma-treated fabrics showed more efficient desizing results when compared with untreated fabrics. Furthermore, the desizing effluent from the treated fabric gave lower TOC, COD and BOD values.

Acrylic Resins↗
PubMed1998

Oligosaccharide polyesters from roots of Polygala glomerata.

Seven new sucrose and oligosaccharide esters, glomeratoses A-G, together with four known compounds, 3-O-[(E)-3,4,5-trimethoxycinnamoyl]-beta-D-fructofuranosyl-(2-->1) - (6-O-benzoyl)-alpha-D-glucopyranoside, 3-O-(E)-sinapoyl-beta-D-fructofuranosyl-(2-->1)-[6-O-(E)-sinapo yl]-alpha-D- glucopyranoside, tenuifoliside C and reiniose G were isolated from the roots of Polygala glomerata. Glomeratoses A-G were elucidated as 3-O-[(E)-3,4,5-trimethoxycinnamoyl]-beta-D-fructofuranosyl-(2-->1) -alpha-D- glucopyranoside, 3-O-(E)-sinapoyl-beta-D-fructofuranosyl-(2-->1)-[6-O-(E)-p- coumaroyl]-alpha-D-glucopyranoside, 3-O-[(E)-3,4,5-trimethoxycinnamoyl]-beta-D-fructofuranosyl-(2-->1) -[6-O-(E)- p-coumaroyl]-alpha-D-glucopyranoside, 3-O-[(E)-3,4,5-trimethoxycinnamoyl]-beta-D-fructofuranosyl-(2-->1) -[6-O-(E)- 3,4,5-trimethoxycinnamoyl]-alpha-D-glucopyranoside, 1-O-{6-O-[3-O-(E,E)-(beta, beta'-bis-sinapoyl)-beta-D-fructofuranosyl]}-alpha- D-glucopyranoside intramolecular ester, 1-O-(E)-p-coumaroyl-(3-O-benzoyl)-beta-D- fructofuranosyl-(2-->1)-[beta-D-glucopyranosyl-(1-->2)]-[6-O-acetyl-beta -D- glucopyranoysl-(1-->3)]-[4-O-(E)-feruloyl]-(6-D-acetyl)-alph a-D- glucopyranoside, 1-O-(E)-p-coumaroyl-(3-O-benzoyl)-beta-D-fructofuranosyl-(2-->1)-[ beta-D- glucopyranosyl-(1-->2)]-[6-O-acetyl-beta-D-glucopyranoside-(1-->3)]-{4-O - [4-O-beta-D-glucopyranosyl-(E)-feruloyl]}-[6-O-(E)-p-coumaroyl+ ++]-alpha- D-glucopyranosyl, respectively, on the basis of chemical and spectral evidence.

Carbohydrate Conformation↗
PubMed2002

Hybrid dendritic-linear polyester-ethers for in situ photopolymerization.

Novel first through fourth generation hybrid dendritic-linear copolymers, composed entirely of building blocks known to be biocompatible or degradable to natural metabolites in vivo, are described. Specifically, these copolymers are composed of poly(ethylene glycol), glycerol, and succinic acid and are synthesized using a divergent approach in high yield. A photo-cross-linkable derivative of this copolymer successfully seals 4.1 mm corneal lacerations. The mechanism of tissue repair is likely one of physical entrapment where an interpenetrating network (IPN) is formed between the cross-linked copolymer and the tissue.

Eye Injuries↗
PubMed2003

New bioactive diterpene polyesters from Euphorbia decipiens.

A reinvestigation with a modified extraction procedure of Euphorbia decipiens resulted in the isolation and structure elucidation of three new myrsinane-type diterpene esters (1-3). The structures of compounds 1-3 were elucidated by spectroscopic data interpretation. Compound 1 showed inhibitory activity against prolyl endopeptidase (PEP), whereas compound 2 exhibited DNA-damaging activity in a mutant yeast bioassay.

Chryseobacterium↗
PubMed2000

Physical and mechanical behavior of electron-beam irradiated and ethylene oxide sterilized multiblock polyester.

The effect of two sterilization treatments (electron-beam radiation and ethylene oxide gas) on the structure and mechanical properties of a multiblock copolymer were investigated to establish the effects of the sterilizing procedures on potential biomedical material. The material was exposed for different radiation doses in order to find an optimum dose of electron-beam radiation. Characterization techniques employed include gel permeation chromatography, infrared spectroscopy, differential scanning calorimetry, dynamic mechanical thermal analysis and tensile testing. The optimal dose of radiation at which no change in structure and mechanical properties occurred was found as 25 kGy. Ethylene oxide gas treatment also did not affect the structure and properties of the polymer and it can be recommended as an alternative sterilization route for the studied polymer.

Journal Article↗
PubMedDate not supplied

Intrinsic structural failure of polyester (Dacron) vascular grafts. A general review.

Intrinsic structural failure of Dacron prostheses is a late exceptional complication, resulting from a loss of structural integrity of the graft. The authors report six cases of non-anastomotic false aneurysms in the mid-portion of a vascular Dacron graft, observed at a mean of 12 years after insertion. It concerns four femoro-popliteal bypass grafts, one cross-over graft and a branch of a bifurcated aorto-bifemoral graft, implanted between 1980 and 1990. This represents 0.2% of all vascular Dacron grafts implanted in authors' department since 1980. The degenerated prosthesis was excised, and a new bypass graft was inserted. In three cases, histological analysis revealed a foreign body giant cell reaction against fragmented Dacron fibers. In none of the cases there was evidence of graft infection. The authors discuss the evidence and etiopathogeny of this late, unusual complication, inherent to the Dacron graft material. The most probable causative factor is material fatigue, leading to gradual breakdown and fragmentation of individual fibers, and subsequent biodegradation of the basic material. Such an intrinsic weakness of prosthetic fabric has only be observed in first and second generation Dacron grafts.

Aneurysm, False↗