Synthesis and ESCA surface studies of octadecyl chain‐extended polyurethanes

Rahman, Ron; Ratner, Buddy D.

doi:10.1002/pola.1989.080270815

Cited by 25 publications

(14 citation statements)

References 14 publications

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“…The reason is that the surface of HTPB-based PU is more hydrophobic than the other two types of PU, which has been explained in Section 3.2. By the way, it has been reported that alkyl-grafted SPUs or the introduction of long alkyl side chain onto a PU have been shown to reduce platelet deposition and enhance in vitro albumin adsorption [18,19]. So that more soft segment dispersed on the polymer surface than the other two types of PUs which may be the reason for the lowest F/A molar ratio of HTPB-based PU.…”

Section: Contact Angle Measurementmentioning

confidence: 99%

“…In order to examine the C=O/C=C ratio on the air face composition, ESCA analysis was used to calculate the ratio of oxygen to carbon atom (O/C) [17,18]. The peak of the oxygen element, which appears at 534 eV on ESCA spectra, indicates that the hard segment is on the PU polymer surface, while that of carbon element appears at 287 eV, and this means that the soft segment is on the surface.…”

Section: Esca Measurementmentioning

confidence: 99%

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Surface composition and protein adsorption of polyurethane membrane

Huang

Lai

1999

Journal of Membrane Science

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Membranes of uncomplexed polyurethanes (PUs) were prepared by hydroxyl-terminated polybutadiene (HTPB), 4,4 Hdicyclohexylmethane diisocyanate (H 12 MDI) and 1,4-butane diol (1,4-BD). While complexed PUs were prepared by using Nmethyl diethanol (MDEA) as the chain extender of which the tertiary amines were complexed with cupric ions. Molar ratio of protein adsorption of ®brinogen to albumin (F/A molar ratio) on polymer surface was measured. The F/A molar ratio was affected by surface composition. The surface composition was identi®ed by ESCA measurement and quanti®ed by the absorption ratio of carbonyl group to butadiene group (C=O/C=C ratio) on the FTIR±ATR spectra. Low F/A molar ratio and high contact angle were found on these PUs. The F/A molar ratio was decreased by the increase of soft segment or C±H bond dispersed on the surface. Frequency difference (Á#) and shiftment, hydrogen bonding index (HBI) and glass transition temperature difference (ÁT g ) as a measure of phase homogeneity and the average strength of interpolymer hydrogen bonds were utilized to study the change of surface composition and intermolecular interaction of the prepared PUs. The effect of hard segment content, cupric chloride content on the surface composition and F/A molar ratio were investigated. #

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Section: Contact Angle Measurementmentioning

confidence: 99%

Section: Esca Measurementmentioning

confidence: 99%

Surface composition and protein adsorption of polyurethane membrane

Huang

Lai

1999

Journal of Membrane Science

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“…1,2 Many studies have aimed at discussing the effect of surface composition of PUs on the protein adsorption and the platelet adhesion. [3][4][5] The adsorption of fibrinogen on the material's surface increases the platelet adhesion. 6 It is observed that the albumin-coated surfaces exhibit remarkable inhibition of platelet adhesion.…”

Section: Introductionmentioning

confidence: 99%

Structure-protein adsorption relationships of polyurethanes

Huang¹,

Ou²,

Chao³

et al. 1999

J. Appl. Polym. Sci.

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A series of hydroxyl-terminated polybutadiene (HTPB) and 4,4Ј-dicyclohexylmethane diisocyanate (H 12 MDI)-based polyurethanes (PUs) with different molecular weight, hard-segment content, or 4-vinyl pyridine content (4-VP content) were synthesized by solution polymerization. Protein adsorption ratio of fibrinogen to albumin (F/A molar ratio), which was adopted as the indicator of blood compatibility, was measured. The F/A molar ratio on the film's surface was affected by surface composition. The surface composition was quantified by carbonyl group to butadiene group (CϭO/CϭC) adsorption ratio on FTIR-ATR spectra and oxygen to carbon atom (O/C) ratio, which was determined by ESCA. PUs with more hard-segment content on the surface (i.e., high CϭO/CϭC ratio) possess more fibrinogen adsorption and less albumin deposition (i.e., high F/A molar ratio). The CϭO/CϭC ratio, hydrogen-bonding index (HBI value), frequency shift and difference (⌬), glass transition temperature of soft segment (T g s) as a measure of homogeneity, average strength of interpolymer hydrogen bonds, and interpenetrating networks (IPNs) were utilized to study the surface composition, intermolecular attraction, and IPN formation of the prepared PUs. The effect of hard-segment content, molecular weight or 4-VP content on the F/A molar ratio were investigated. The results of FTIR and ESCA explain well the surface composition, and hence, the F/A molar ratio as well.

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“…1,2 Segmented thermoplastic PU has been extensively studied. However, the investigation on crosslinked PU (CPU) has been still limited.…”

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confidence: 99%

Crosslinked Polyurethane-Based Gels

Phung

Schacht

Prez

et al. 2003

Polym J

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ABSTRACT:Crosslinked polyurethanes (CPUs) were synthesized by reaction of (ethylene oxide-propyleneoxideethyleneoxide) (EO-PO-EO) triblock copolymer with diisocyanate and a low molecular weight triol as a crosslinking agent. The short diol was used as a chain extender. The effect of some factors such as the nature and content of PAOs, short diol chain extender and triol crosslinking agent on the phase separation of CPUs was studied by infrared spectroscopy (IR) and differential scanning calorimetry (DSC). The presence of amine group-containing compounds favors the phase separation of CPUs. The swelling behavior of CPUs in the different media such as aqueous solution and ethanol (EtOH)-water mixture has been investigated. The CPUs show the negatively thermosensitive swelling behavior. The collapsing swelling process in response to the change in environmental temperature was observed in CPUs prepared from EO-PO-EO triblock copolymer having a commercial code L92. In a EtOH-water mixture, CPUs reached the maximum swelling degree at the ratio EtOH/water 80/20 at the whole range of the environmental temperature due to the coupling effect.

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Synthesis and ESCA surface studies of octadecyl chain‐extended polyurethanes

Cited by 25 publications

References 14 publications

Surface composition and protein adsorption of polyurethane membrane

Surface composition and protein adsorption of polyurethane membrane

Structure-protein adsorption relationships of polyurethanes

Crosslinked Polyurethane-Based Gels

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