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Processors set increasing demands on compoundsProcessors set increasing demands on compounds

July 1, 2006

6 Min Read
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In 2005, sluggish growth in the compounding sector dogged European producers while the Asian compounds market continued its expansion.

These results, as reported by market researchers at Applied Market Information (AMI; Bristol, England), as well as the fact that the number of integrated polymer producers/compounders dropped from 135 to 95 since 2002 while independent European compounders jumped from 41 to 585 during the same period, tell a story that compounders in developed regions must-and are-looking at ways to protect their competitiveness.

According to AMI, the bulk of European processors buy ready-to-use compounds rather than hassle with dosing individual components (additives, fillers, colorants) themselves.

One area processors see possible savings is in the strength of compounds and masterbatches they process. J. Carlos Caro, project manager at additive and color batch compounder Grafe Color Batch (Blankenhain, Germany) says highly loaded masterbatches and compounds are playing an important role (June 2005 MPW).

"With the increasing costs of polymers due to oil price instability, processors are asking for masterbatches that reduce the amount of carrier and increase the active ingredient," Caro says. As well as the reduction of carrier polymer, the higher content materials offer shipping and storage cost savings which are also attractive, he says.

"The processor can reduce his overhead by switching to higher concentrate materials. Margins can be increased and the customer can earn more money on the final product," Caro says.

He gives as one example of a price calculation a UV-stabilizer masterbatch which in standard delivery would contain 12% HALS, 6% UV absorber, 3% anti-oxidants all delivered in a 79% low density polyethylene (LDPE) carrier. By switching to a content of 24% HALS, 12% UV absorber, 6% anti-oxidant in a LDPE carrier reduced to 58%, the processor gets a cost per kg savings of 55% over the standard masterbatch. The order and shipping is 10 tonnes rather than 20 tonnes for a savings on transport and warehousing and the dosage is reduced by 50%.

Caro warns, however, that higher concentrations of materials cannot simply be doubled or tripled. Each individual masterbatch needs to be considered to determine if such increases are feasible. Also processors generally need to switch from volumetric to gravimetric dosing to ensure exactness.

"Many processors don''t dose high concentrations because they are afraid of inaccuracy in their measurements. They look to their compounders for this know-how in order to increase efficiencies and eliminate dusting problems," he says. Other materials Grafe is seeing in demand in high concentrations today are slip agents, anti-stat, nano fillers up to 70% loadings for flame retardancy, and optical brighteners for greenhouse films.

Paul Strasser, marketing/sales manager at Dutch compounder Addcomp Holland (Nijverdal) is also seeing demand for high concentrations of additive blends. Through what Strasser says is the company''s proprietary technology with its in-house designed and constructed extruders, it is able to provide easy-to-use one-pack systems that allow more accurate dosing compared to liquids, powders, and paste options. Now the company is offering additive filled materials up to 70% but believes it can further reduce the amount of carrier to provide 80% active ingredients in the future.

Addcomp takes the input of its customers and designs additive packages to their specifications based on the right balance of materials, he says. For polymer producers and integrated compounders Addcomp is also producing compacted pellets of additive blends that do not contain a polymer carrier but consist of 100% active ingredient.

The company has developed an extrusion process for high concentrations of liquid and low melt anti-fog and anti-slip agents which will migrate through the physical matrix after processing. This process eliminates lumping problems in humid or hot climates, increases the shelf life of the blend, and allows up to 80% ingredient content.

Mark Edwards, European sales manager for building and construction plastics at additives producer and compounder Holland Colours (Apeldoorn, Netherlands) confirms that many processors see higher concentrations of materials as a means of cutting costs and helping competitiveness.

The company''s beaded coloring system Holoprill, for weather and light fastness of extruded PVC siding and profiles in particle size of 1-2 mm, contains about 50% organic or up to 80% inorganic pigment. He says the concentrates at this level allow a very good pigment dispersion, batch-to-batch consistency, free-flow, and cost effective performance.

Additive producer Baerlocher (Unterschleissheim, Germany) last year introduced melt pastilles of calcium-based PVC stabilizers that allow high dosing levels because the ingredients are compacted with wax rather than a resin carrier, says Jörg Fröhlich, PVC additives development manager. Rather than pressed as in the Addcomp process, the active ingredients here are melted into the matrix yet in a dry blend it shows no negative melt history, Fröhlich says.

Other demands

There is no single thing that compounders agree on that they want in order to improve their business competitiveness, says Beat Sturzenegger, CEO of compounding equipment producer Buss (Pratteln, Switzerland). "There are different demands depending on the type of customer out there," Sturzenegger says. "Polyolefin compounders and producers want higher output, while engineering resin compounders tend to want specialized solutions for their particular materials."

Energy savings are starting to be part of this decision process but not yet the deciding factor, he says. Buss installed one of its Quantec kneaders last month, which Sturzenegger says offers a three times improvement in output over comparable twin-screw compounding extruders, at masterbatcher Grafe Color Batch. Caro says this new unit is expected to offer additional efficiencies for the production of conductive compounds.

Prior to this installation, Grafe operated an all twin screw co-rotating extruder park from equipment maker Leistritz (Nurnberg, Germany). However, to achieve the high content filler level of additives Caro says Grafe configured and designed its own screws.

Competitor Coperion Werner & Pfleiderer (Stuttgart, Germany) is seeing requests from compounders for more flexibility in the equipment they source. The company has therefore introduced a modular concept of its complete compounding plants offering everything from material supply equipment through pelletization.

Last month the company introduced this concept with its ZSK 32 MEGAcompounder PLUS system at the NPE. The modular concept offers advantages of customized plant designed according to customer specifications. Coperion engineers create modules which can be pre-assembled and wired in a steel frame with all pipes installed, ready for shipment in a 40-ft container.

This is a similar concept which several film and sheet extrusion equipment producers previously employed. Reifenhäuser (Troisdorf, Germany), in 2001, started delivering a cast and thermoforming sheet line boxed up in two 20-ft containers as well as film equipment producer Macchi (Venegono, Italy) offers some of its processing equipment fully pre-mounted and pre-tested, in addition to being containerized.

Robert Colvin [email protected]

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