PEN manufacture

The iron-centred redox properties of a ferrocene derivative similar to that shown below are the basis of the ExacTech pen, manufactured by Medisense Inc. The pen s function is to measure glucose levels in people with diabetes. The iron... 

M. Sokuler and L. A. Gheber, Nano fountain pen manufacture of polymer lenses for nano-biochip applications. Nano Lett., 6, 848 (2006),... 

In the early 1990s interest developed in the packaging material polyethylene naphthalate (PEN), a close cousin of PET. PEN has thermal stability 20°C higher than PET. Kodak had samples of the material sifting in its labs from the makers Teijin in Japan, as early as the beginning of the 1970s. Teijin is still the premier producer of PEN film and plastic today, and is involved with DuPont on the film manufacturing side. 

Chitin films can be manufactured from DMAc solutions or by other approaches, for example, blend films of beta-chitin (derived from squid pens) and poly(vinyl alcohol) (PVA) were prepared by a solution casting technique from corresponding solutions of beta-chitin and PVA in concentrated formic acid. Upon evaporation of the solvent, the film having 50/50 composition was found to be cloudy [224]. 

In reinforcing materials double-dipped polyesters for improved tire durability, plasma-treated yams for improved bonding in tire, and increased usage of aramid fabric as belt and application of PEN are the areas where manufacturers are showing interest. Introduction of new styles of steel wire geometry for improved mbber to metal adhesion and new steel wire coating formulations for improved mbber to metal bonding are other focused areas of development. 

Processing and Uses. Polystyrene is an outstandingly good injection molding material. In this process the material is melted and forced through dies into a mold where it cools and solidifies. The process is very adaptable and is particularly suitable for the mass-production of small articles. Components for the electrical industry, objects for everyday use (buttons, combs, tube tops, fountain pens, etc.) and also articles for the military field (components for detonators in grenades, parts of gas-masks etc.) were manufactured in this way at that time. 

PET is produced continuously on a large scale as well as in small-sized batch plants. Currently, batch plants are mainly used for specialities and niche products. Batch plant capacities span the range from 20 to 60 t/d. Depending on process conditions, process technology and the desired PET grade, six to ten batches per day are commonly manufactured, each with a capacity of between 1.5 and 9.01. Batch plants are often designed as multi-purpose plants in which also PBT, PEN and different co-polyesters are produced. 

The manufacture of polyethylene naphthalate) (PEN) is carried out using dimethyl 2,6-naphthalene dicarboxylate (NDC) and EG and is similar to the manufacture of PET from DMT. The IV after the melt is typically in the range of 0.5... 

Although the superior properties of PEN have been known for many years, the unavailability of the naphthalate monomer has delayed the development of commercial markets, until relatively recently (1995) when the Amoco Chemical Company offered high purity naphthalene-2,6-dimethyl dicarboxylate (NDC) in amounts of up to 60 million pounds per year. This diester is produced by a five-step synthetic route, starting from the readily available compounds, o-xylene and 1,4-butadiene [3], Prior to this, the NDC diester was obtained by extraction of 2,6-dimethylnaphthalene (DMN) from petroleum streams, where it was present in relatively low abundance. Oxidation of DMN to crude 2,6-naphthalene dixcarboxylic (NDA) is conducted by a similar process to that used for conversion of p-xylcnc to purified terephthalic acid (TA), crude NDA is esterified with methanol, and is then distilled to yield high purity NDC. Other companies (e.g. the Mitsubishi Gas Chemical Company) followed Amoco s introduction with lesser amounts of NDC. Teijin [4] has manufactured PEN for many years for its own captive uses in films. 

There are two major manufacturing routes for PEN and PET, i.e. (1) an ester, or (2) an acid process, named according to whether the starting monomer is... 

Figure 9.3 Star diagram illustrating the improved properties of PEN when compared to PET PEN, black PET, white. From manufacturer s literature published by BP Chemicals and reproduced with permission... 

The monomer used for the preparation of PEN is dimethyl-2,6-naphthalenedicar-boxylate (NDC) or 2,6-naphthalenedicarboxylic acid (NDA). During the long development time, several synthetic methods were developed and the manufacturing processes were improved, which finally reduced the cost for the commercialization of PEN [5-10], The main synthesis routes are described in the following. 

Figure 10.2 Manufacturing process used to produce PEN resin...

CONTINUOUS PROCESS FOR THE MANUFACTURE OF BI AXIALLY ORIENTED PEN FILM... 

Figure 10.3 Manufacturing processes used to produce PEN films (a) simultaneous (b) sequential (MD, machine direction TD, transverse direction)...

PEN is used in manufacturing electrochemical lithium ion batteries because it is dimensionally stable and highly resilient [54], It could replace polyethylenimine, which is currently used at unusually high temperatures to cure special inks. PEN is also useful in membrane touch switches (MTSs) where the circuit would be exposed to a high temperature, such as the domes for switches and seat sensors in automobiles. PEN is also particularly suited to a wide range of flexible heaters and low- to intermediate-voltage heaters, such as waterbed heaters and battery heaters. 

PEN films provide specifications that meet the requirements. PEN shows high mechanical properties, low fogging during manufacture and storage, and excellent thermal dimensional stability, and can be made photo-reactive with the gelatin being reactive. Consequently, it is a good support material for advanced photosystems [55, 56],... 

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