A ToF-SIMS investigation of the thermodynamics and bonding of polymeric methylene diphenyl diisocyanate on oxidised aluminium and iron surfaces

Shimizu, Kyoko; Abel, Marie‐Laure; Phanopoulos, C.; Holvoet, Servaas; Watts, John F.

doi:10.1039/c3ra22696d

Cited by 7 publications

(7 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The thermodynamics of pMDI adsorption on aluminum and iron surfaces was also studied by Shimizu. 12 For both aluminum and iron substrates, Langmuir isotherm adsorption behavior was observed over most adsorbent concentrations. However, at concentrations below 1 g L −1 , adsorption did not follow the expected Langmuir isotherm.…”

Section: ■ Introductionmentioning

confidence: 99%

Interfacial Chemistry Investigation of Initial Fouling Conditions in Isocyanate Production: The Antifouling Performance of AISI 316L Stainless Steel

Bevas

Abel

Jacobs³

et al. 2021

ACS Omega

Self Cite

View full text Add to dashboard Cite

The fouling of AISI 316L stainless steel during themanufacture of polymeric methylene diphenyl diisocyanate (pMDI) has been investigated. Studies have been carried out using a laboratory-based rig that simulates the process chemistry of the production plant. A variety of solution concentrations and treatment times have been employed to represent different stages in the production process. Following exposure, steel coupons have been removed and studied by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The thickness of the fouling layer, determined by XPS, is found to vary inversely with exposure time and solution concentration. This is a result of the solubility of the different pMDI derivatives that have been formed at different stages, and a reaction scheme is developed to explain these inverse relationships. ToF-SIMS indicates the formation of metal chlorides as a result of the initial treatment of the steel in the reaction vessel with hydrogen chloride. Fragment ions characteristic of reacted and unreacted pMDI (at m/z = 106 and 132 au, respectively) were used as an indicator of the degree of reacted isocyanate groups within the fouling layer and show a decrease with increasing exposure time, as a result of the formation of intermediates such as amines, ureas, carbodiimides, and uretonimines. The ToF-SIMS data was also processed by principal component analysis (PCA). This generally reinforced the conclusions reached by XPS and ToF-SIMS but, in addition, gave confidence in the repeatability of the analyses with the repeat data (of four analyses) clustering very tightly in the PCA score plots.

show abstract

Section: ■ Introductionmentioning

confidence: 99%

Interfacial Chemistry Investigation of Initial Fouling Conditions in Isocyanate Production: The Antifouling Performance of AISI 316L Stainless Steel

Bevas

Abel

Jacobs³

et al. 2021

ACS Omega

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, because of a strong matrix effect and variability in molecular ionization, it is not easy to quantify data from TOF‐SIMS results: by contrast, XPS is an established semi‐quantitative surface technique. Thus, together, the two techniques can mutually provide insights on molecular adsorption and polymerization onto solid substrates …”

Section: Introductionmentioning

confidence: 99%

ToF‐SIMS study of stages in the electrochemical growth of insulating poly(o‐aminophenol) films

Carbone

Ciriello

Salvi

et al. 2016

Surface & Interface Analysis

View full text Add to dashboard Cite

Previous XPS investigations of insulating poly(o‐aminophenol) (PoAP), electrosynthesized by cyclic voltammetry on Pt substrates, revealed the formation of a thin film of about 7 nm of thickness, firmly adherent onto the electrode surface and stable even under Ultra High Vacuum (UHV) conditions. A constant repeat formula made of alternating quinoneimine and monomer units was derived with polymer chains terminating as carbonyl‐type groups. Based on these findings, we have continued our investigation on insulating PoAP by employing time‐of‐flight SIMS whose superior surface sensitivity is well‐known. The aim was to corroborate the polymer structure with particular reference to the top surface layers in view of possible bio‐applications and to understand the possible way of interaction with the underlying platinum electrode surface. In order to do this, we analyzed PoAP films grown at different levels of the electrochemical synthesis (1, 5, and 20 scan cycles) and the platinum substrate itself. The individuation of the main characteristic fragments and the behavior of their intensity by varying the stage of the electropolymerization allowed to confirm the polymer structure and the presence of terminating carbonyl groups. Remarkably, from the analysis of the PoAP/Pt interface at the early stage of the polymer formation, it was possible to discern that polymer chains tend to interact with the electrode surface preferentially by the nitrogen atom of the oxidized monomers. Copyright © 2016 John Wiley & Sons, Ltd.

show abstract

“…The adsorption studies were carried out by immersing the HDGS specimens in solutions of different concentration of the adhesion promoter (in a range of 0.001–1 mole/litre); adsorption isotherms were determined by assessing the uptake of the adsorbate, as a function of solution concentration, by X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS); full details of sample preparation can be found in …”

Section: Methodsmentioning

confidence: 99%

“…Physisorption forms multilayers, whereas chemisorption is limited to monolayer coverage . Therefore, in the case of chemisorption, there is a plateau in the adsorption isotherm, and a variety of types of chemical adsorption can be identified such as the Langmuir, Temkin and Freundlich …”

Section: Introductionmentioning

confidence: 99%

The role of the adhesion promoter in a model water‐borne primer

Adhami

Abel

Lowe

et al. 2014

Surface & Interface Analysis

View full text Add to dashboard Cite

In the search for improvements in the environmental credentials of the organic coatings industry, several different aspects are currently being addressed, including the reduction of volatile organic compounds, development of UV curable coatings and the reduction of potentially hazardous components in coating formulations. The performance of a novel water‐based primer system, applied to alkali cleaned hot dipped galvanized steel, was investigated previously. It was shown that the level of adhesion promoter has a clear effect on durability and performance to the panels painted with the candidate primer and topcoat. Two concentrations of adhesion promoter were used, and the formulation with the higher concentration exhibited better coating longevity. The aim of this work is to understand the role of adhesion promoter in the primer formulation, particularly the manner in which it interacts with the substrate and the topcoat. This paper will describe the distribution of the adhesion promoter across the primer layer considering the possible opportunities of such a component enhancing the primer interaction at either interface. Copyright © 2014 John Wiley & Sons, Ltd.

show abstract

A ToF-SIMS investigation of the thermodynamics and bonding of polymeric methylene diphenyl diisocyanate on oxidised aluminium and iron surfaces

Cited by 7 publications

References 24 publications

Interfacial Chemistry Investigation of Initial Fouling Conditions in Isocyanate Production: The Antifouling Performance of AISI 316L Stainless Steel

Interfacial Chemistry Investigation of Initial Fouling Conditions in Isocyanate Production: The Antifouling Performance of AISI 316L Stainless Steel

ToF‐SIMS study of stages in the electrochemical growth of insulating poly(o‐aminophenol) films

The role of the adhesion promoter in a model water‐borne primer

Contact Info

Product

Resources

About