title: Real Time NMR Analysis of Melamine Formaldehyde Resin Reactions

authors: Wang, Yuan

subjects: Melamine

abstract: This investigation was carried out on behalf of the Momentive Specialty Chemicals Pty Ltd, Mt Maunganui. The aim of the investigation was to develop a method to analyse the formation of melamine formaldehyde resins via an in situ real time NMR experiment leading to quantitative NMR intensities of the resin up to the stages of its Industrial Resin Endpoint (IRE). 
In order to run an in situ reaction for the melamine formaldehyde resin system and monitor it in real time, both qualitative and quantitative NMR acquisition methods were required. The qualitative method was power gated and used to obtain results in situ and in real time. However to render it quantitative, it was necessary to develop a quantitative method which was initially executed to obtain a conversion factor for relating the qualitative results obtained in the in situ experiment to quantitative results performed by doing inverse gated NMR spectra on a final form of the resin.  The development of this technique required the determination of the longitudinal relaxation times (T1) of the species within the melamine reaction as these were required to derive the necessary repetition rates employed in the NMR acquisition methods.
In general, this project involved the development of  the above mentioned NMR analytical protocols with tailoring to run this type of experiment in a 5 mm NMR tube using a 400 MHz NMR spectrometer whereby previous research on urea and phenol formaldehyde resins and employing identical NMR methodologies had relied on analyses conducted in a 10 mm NMR tube on a 300 MHz NMR instrument. 
As a result, reaction profiles of the melamine resin reaction were obtained during a real time experiment. The reaction profiles of the addition stage of the melamine resin reaction showed that the increase in the methylol melamine species occurs very fast and is justified by the exponential decay of the methylene glycol species corresponding to the formaldehyde solution. The condensation stages of the resin reaction were also observed until the IRE. The reaction profiles of the ether and methylene bridge links are clearly given showing that ether linkages predominate in the addition stage and plateaus, and methylene linkages only increase after the addition stage of the reaction. They provided insight to the reaction progress corresponding to addition and condensation stages of the melamine resin reaction.

text: Real Time NMR Analysis of Melamine Formaldehyde Resin Reactions This investigation was carried out on behalf of the Momentive Specialty Chemicals Pty Ltd, Mt Maunganui. The aim of the investigation was to develop a method to analyse the formation of melamine formaldehyde resins via an in situ real time NMR experiment leading to quantitative NMR intensities of the resin up to the stages of its Industrial Resin Endpoint (IRE). 
In order to run an in situ reaction for the melamine formaldehyde resin system and monitor it in real time, both qualitative and quantitative NMR acquisition methods were required. The qualitative method was power gated and used to obtain results in situ and in real time. However to render it quantitative, it was necessary to develop a quantitative method which was initially executed to obtain a conversion factor for relating the qualitative results obtained in the in situ experiment to quantitative results performed by doing inverse gated NMR spectra on a final form of the resin.  The development of this technique required the determination of the longitudinal relaxation times (T1) of the species within the melamine reaction as these were required to derive the necessary repetition rates employed in the NMR acquisition methods.
In general, this project involved the development of  the above mentioned NMR analytical protocols with tailoring to run this type of experiment in a 5 mm NMR tube using a 400 MHz NMR spectrometer whereby previous research on urea and phenol formaldehyde resins and employing identical NMR methodologies had relied on analyses conducted in a 10 mm NMR tube on a 300 MHz NMR instrument. 
As a result, reaction profiles of the melamine resin reaction were obtained during a real time experiment. The reaction profiles of the addition stage of the melamine resin reaction showed that the increase in the methylol melamine species occurs very fast and is justified by the exponential decay of the methylene glycol species corresponding to the formaldehyde solution. The condensation stages of the resin reaction were also observed until the IRE. The reaction profiles of the ether and methylene bridge links are clearly given showing that ether linkages predominate in the addition stage and plateaus, and methylene linkages only increase after the addition stage of the reaction. They provided insight to the reaction progress corresponding to addition and condensation stages of the melamine resin reaction.

year: 2012

title: Book Review: The Japanese and Europe: images and perceptions

authors: Swale, Alistair

subjects: book review

abstract: This article reviews the book: “The Japanese and Europe: images and perceptions”, edited by Bert Edstrom.

text: Book Review: The Japanese and Europe: images and perceptions This article reviews the book: “The Japanese and Europe: images and perceptions”, edited by Bert Edstrom.

year: 2002

title: Weaving kaupapa Māori and e-Learning

authors: Neal, Terry

subjects: New Zealand

abstract: This paper describes the creation and design of an online professional development course that aims to help educators in New Zealand to weave kaupapa Māori and e-Learning approaches together. The team sought to model weaving of kaupapa Māori and e-Learning approaches in how they worked together and the educational design for the material. The authors propose that educators with these skills are crucial if we are to effectively meet the needs of Māori learners, more than that, of all New Zealand learners, in the 21st century.

text: Weaving kaupapa Māori and e-Learning This paper describes the creation and design of an online professional development course that aims to help educators in New Zealand to weave kaupapa Māori and e-Learning approaches together. The team sought to model weaving of kaupapa Māori and e-Learning approaches in how they worked together and the educational design for the material. The authors propose that educators with these skills are crucial if we are to effectively meet the needs of Māori learners, more than that, of all New Zealand learners, in the 21st century.

year: 2006-09