Thursday, February 15, 2007

Review compares rubber and TPEs

A review covering thermoplastic elastomers that have the elastic behaviour of rubber and the processability of thermoplastics, includes comparisons between the two material types.

Thermoplastic elastomers (TPEs) have the elastic behaviour of rubber and the processability of thermoplastics. The Freedonia Group has forecast that demand will expand by 6.4% per year to around 2.15 million tons in 2006. There is potential for these new, exciting materials to expand into the much larger thermoset rubber markets.

This latest Rapra Review Report, Developments in Thermoplastic Elastomers, includes comparisons between the two material types.

The review covers the structure, chemistry, performance and application of TPEs for the most recent 8 year history since the previous Rapra Review Report by J.A.

Brydson was published.

There are three major types of TPE: block copolymers, rubber/plastic blends and dynamically vulcanised rubber/plastic alloys known as thermoplastic vulcanisates.

The chemistry of these materials and how their unique properties are achieved are discussed in this review.

There are many developments taking place in this field.

These are discussed in the review.

Specialist grades are being introduced for specific applications and with unique properties, such as softness or processability.

New types of styrene block copolymers have improved high temperature ageing, fluid resistance, elastic recovery and set.

New block copolyester TPEs have better blow moulding processability, softness and high dynamic flexing fatigue performance.

One of the advantages of TPEs over thermoset rubbers is that they can be processed by standard plastics processing methods.

This review considers rheology, injection moulding, extrusion, blow moulding, thermoforming and other secondary processes.

There are a variety of factors to consider when designing with TPEs, which are discussed here.

One particular advantage is in combining components of a product as TPEs can be co-injected or used in overmoulding, reducing assembly steps.

Developments in thermoplastic elastomers will be of interest to producers of TPEs, designers and manufacturers.

The review is accompanied by around 400 abstracts from papers and books in the Rapra Polymer Library database, to facilitate further reading on this subject.

A subject index and a company index are included.

The author of the review, Ken Kear, has worked as a Senior Applications Specialist with Advanced Elastomer Systems.

He has over 20 years of extensive experience in developing and working with thermoplastic elastomers.

He is a member of the Society of Plastic Engineers (SPE).

Twin screw compounder acquired for development

A leading polymer research and test house has ordered a new twin screw compounder from Rondol Technology in order to enhance its capabilities in thermoplastics compounding development.

Rapra Technology, Europe's leading polymer research and test house, has ordered a new twin screw compounder from Rondol Technology in order to enhance its capabilities in compounding and compound development. The new 21mm twin screw machine will initially be used in work to establish new nanofilled thermoplastic compound technology. Possible applications are set to include flame retarded products; biodegradable materials, and barrier membrane materials.

The Rondol compounder will also be available for compound development and client consultancy.

Business manager for Polymer Processing at Rapra Technology, Emyr Peregrine explains that 'our new Rondol machine offers an ideal combination of flexibility, output and power input.

We are very fortunate to have such supplier expertise close by - in Stone, Staffordshire - and are now looking forward to expanding our operations in the nanofiller compounding area.' A number of Rapra partner companies are already set to participate in the new nanofiller compounding work and Rapra welcomes interest from other companies.

Rapra Technology has been investing across the board; in analytical, testing and design equipment, as well as laboratory sized processing machinery.

Overall some œ400,000 in capital purchasing was released for spending at Rapra's Shawbury HQ earlier in the summer of 2003, much of this in the analytical services area.

The investment was the biggest ever made by the consultancy over the course of its 80-year history.

The new capabilities will strengthen Rapra Technology's position at the forefront of independent polymer analysis in Europe.

Rapra Technology Chief Executive Andrew Ward notes that recent investments have been enabled by the new structure of the company.

'At the time of the Management Buy Out in July 2002 we promised investment in the fundamentals.

Polymers and composites expand applications range

Innovative polymers and composites, such as long glass-fibre reinforced thermoplastics, are dramatically broadening the range of applications and commercial production of thermoplastics.

Innovative polymers and composites are dramatically broadening the range of applications and commercial production of thermoplastics. Made from both well-established and novel polymers, materials such as long glass-fibre reinforced thermoplastics, wood-plastic composites (WPC) and nanocomposites are experiencing high growth despite being relatively developmental markets. Nanocomposites are forecast to be the highest growth market, but from a rather small base.

WPCs, on the other hand, are a profit-generating market in North America although their penetration in the Europe is just beginning.

Brian Balmer, Industry Analyst from Frost and Sullivan explains, 'The high cost and lack of a mass market has restrained the uptake of these materials thus far, but the WPC market is set to take hold in Europe and Asia as a growing number of extruders emulate the U.S.

and adopt WPC in construction applications.' Since Europe lacks a decking market, WPC technology uptake will take place in a different manner in comparison with the United States.

Focus will be on specialised applications and intricate products such as window profiles, skirting boards and some furniture applications.

Thermoplastic composites are expected to replace metals and thermosets in numerous applications as they offer remarkable advantages over these traditional materials.

Durable, light, environmentally-friendly and chemically stable, composites also offer a myriad of possibilities in terms of optimising materials to suit applications.

This adds further to their attractiveness.

LFT is one of the fastest growing plastics industry sectors and automotive applications account for over 95 per cent of the worldwide demand.

In Europe, an annual growth rate of 10-12 percent was observed during the period 1999-2002.

'The automotive industry is the main driver for the European long fibre reinforced thermoplastic (LFT) market, which has been expanding faster than other LFT markets,' notes Balmer.

'New applications include under body panels, front-end modules, and door panels.' Acceptance of nanocomposites has been relatively slow despite the initial promise of 'a dream material for the 21st century.' Nevertheless, the market is expected to pick up rapidly in the near future.

While carbon nanofibres and nanotubes are currently under development, nanoclays are already finding applications in high barrier resins for food packaging and in some automotive applications.

'Ongoing R and D efforts, growing demand for conductive compounds, miniaturisation of electronics parts, improvements in processing machinery and the development of new applications will open more avenues for these materials,' adds Balmer.

Continuous product improvement and innovation hold the key to the further development of innovative composites.

As globalisation and consolidation increase, developing new markets, both in terms of new end users and geographic expansion, is crucial.

Lowering cost bases, speeding up innovation, and building expertise will help LFT suppliers to attract/retain automotive end users.

Companies also need to enhance their customer services, and technical support.

In the WPC market, participants are increasing marketing budgets to raise awareness and adhering to building industry standards to expand revenues.

Licensing, formation of strategic partnerships, and acquisition can help new companies build market share.

In the meantime, nanocomposites suppliers are focussing on developing new products through the compounding process.

Efforts are on to toughened nylon nanocomposites for injection moulding and high-viscosity nanocomposites for blow moulding.

Engineering plastics improve semiconductors

Many semiconductor manufacturers have recently raised concerns over the availability or extremely long lead times for engineering plastics, but a reeadily available material offers better performance.

Victrex continues to make strategic investments in its supply chain, technical and market support, which enable it to offer readily available high performance materials to customers anywhere in the world. These investments are particularly appealing to semiconductor fabs who are currently facing issues over the availability of other engineering plastics. This positions Victrex and the Victrex PEEK family of products as ideal solutions for end users seeking stable supplies of high quality, high performance materials.

Many fabs have recently raised concerns over the availability or extremely long lead times for engineering plastics (such as certain PPS grades) for use in CMP (chemical mechanical planarization) retaining rings.

Victrex PEEK offers proven superior performance in these applications.

Victrex currently supplies Victrex PEEK polymer to a range of wafer fabrication facilities across the world, including facilities in Europe, China, Japan, Korea and Taiwan, through a network of fabricators.

'We've been using Victrex PEEK polymer for the rings for a number of years and our customers are very pleased with the results,' said Bill Kalenian, engineering project manager at Strasbaugh.

'Victrex PEEK polymer is widely acknowledged as one of the premier high-performance thermoplastic materials for CMP rings because of its unique range of properties including inherent purity, strength, chemical resistance, and wear resistance.

Because Victrex PEEK polymer can be machined to extremely tight tolerances and is compatible with process components such as slurries, it has proven ideal for CMP rings, affording more wafer passes during fabrication - resulting in lower downtime and lower cost per wafer.' Strasbaugh purchases the Victrex PEEK polymer blanks from CDI Seals in Humble, Texas, USA.

* test results Revealed - 'One of the key drivers in this area is developing better, longer-wearing CMP rings to match the advancing performance of other critical CMP equipment consumables that complement the CMP head,' said John Walling, Victrex Americas semiconductor manager.

'Materials used in CMP rings in the past have included PPS, but wear tests reveal that CMP rings made from Victrex PEEK polymer have a useful lifetime of up to 2.5 times when compared to PPS.

At Victrex, we are strongly aware of the need for compatible long-life parts and are continuing to develop our materials in line with these technology advances.' Walling continued: 'In the semiconductor sector and in particular CMP retaining rings, our high performance polyaryletherketone material is often the difference between process success and failure.' He said: 'We have customers in the United States and Asia that have switched from PPS to Victrex PEEK polymer because of our application expertise and the product high performance.

Victrex PEEK polymer-based CMP rings enable more wafer passes during fabrication, resulting in lower downtime, and lower cost per wafer.' * Victrex's supply chain strategy - 'The importance of the security of supply in the semiconductor sector cannot be underestimated,' said Blair Souder, commercial director at Victrex.

'It's essential that semiconductor fabs have the material they need when they need it.

Wafer fabs are 24x7 facilities that need a constant supply of high quality, batch-consistent materials.

If a material is unavailable, the cost of delays is immeasurable.

It's not only that the wafer is delayed, but the subsequent effect in the consumer market as the end-product release date is pushed back is often critical.' Assurance of supply and investing ahead of demand has always been part of Victrex's business strategy.

The company is self-sufficient in the manufacture and supply of both Victrex PEEK polymer and its key monomers.

Victrex has made significant investments in two key components of its supply chain.

First, Victrex has backward integrated its raw material supply chain to better control quality and availability for its polymerization facilities.

This was achieved primarily by acquiring, and subsequently upgrading, these facilities.

Second, the company has continually added capacity ahead of demand to ensure a continual supply to customers.

The most recent investment is another Victrex PEEK polymer plant, currently under construction, which will bring the company's total capacity to more than 4,200 tons.

These investments allow Victrex to better control supply, costs, and quality, and ensure availability to customers.

MS screener provides equal feed distribution

Rotex Europe has announced the installation of the first MS Screener in Europe.

Rotex Europe has announced the installation of the first MS Screener in Europe. Sold and installed in The Netherlands to a very important company (which prefers to keep its anonymity) in the Agro Processing field, the MS Screener is the perfect solution to all screening requirements at high temperatures and large volumes. The MS Screener provides unsurpassed screening performance when exact separations and high efficiencies are required, and maximises product recoveries at material temperatures up to 200andordm; C.

Specifically designed to screen fine products at high capacity, the MS Screener provides excellent screening performance due to equal feed distribution to all screen decks, uniform bed-depth across the entire screen surface and a reduction in screen blinding, due to the use of durable declogging balls.

The stacked, multiple-deck, tray access design allows for individual screen access without the need to remove all decks.

A patented Lift- Rail system enables easy installation and removal of the screen frame.

Access and maintenance are simple with single decks being able to be changed in ten minutes - with all 12 decks changed in just two hours.

The screen deck is sloped to an angle of six degrees, which maximises screen efficiency and meets demanding product specifications.

An easily accessible external drive cartridge allows continuous operation at temperatures up to 200C and is designed for 200,000 hours of service.

The MS Screener utilises a support shaft suspension system with industrial U- joint bearings and no maintenance, low torsion centre springs.

An optional floor-mounted suspension stand is available for installations without overhead support.

Abrasion-resistant steel construction and 'rockbox' landing areas allow for repeated impact on high-wear surfaces.

The MS Screener incorporates a new silicone seal system that press fits into place without adhesives.

The seal is universal throughout the machine providing exceptional sealing between screen decks on fine separations.

A unique sleeveless brush system on the discharge doors eliminates traditional connecting sleeves for quicker screen deck access.

Integral vent connections enable enhanced dust control on dustier materials.

This newly designed product demonstrates that the food industry remains a key market sector for ROTEX EUROPE, in addition to mineral, chemical and plastic applications.