INDUSTRIAL POLYMER SOLUTIONS

Polymers

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Overview

Polymerisation is the first basic step in plastics production. Depending on the monomers, it can be carried out in bulk, in a solution, or in an emulsion.

If monomer solutions are introduced into the reactor, they are first filtered to separate impurities. Filtration is also used after polymerization to recover monomer residues from polymer solutions/suspensions and to return them to the polymerization reactor.

Thermoplastics are an important class of plastic raw materials, like polyamide (PA), polymethyl methaycrylate, polycarbonate, or polyether ether ketone (PEEK). After polymerisation, these materials are either directly granulated for further processing elsewhere, or they are directly melted and processed by extrusion or injection moulding. Our screen changers and melt filter systems are used in this stage.

Our polymerisation solutions

Fibre production

There is an increasing demand for nonwovens for the production of technical textiles, including filter media, textiles for the clothing industry, hygiene articles, etc.

Synthetic fibres form a large share of the raw materials. In addition to the well-known polyesters, nylon and viscose, which is based on natural resources, are used. Polyurethane fibres are essential parts of elastic textiles.

High performance fibres from chemically and thermally resistant polymers, as well as bi- or multi-component fibres, enable new technical applications. In addition to the production of nonwovens, synthetic fibres are used for stabilizing materials, in tyres for example.

To obtain required technical features at minimum material consumption, e.g. for achieving lower flow resistance with low specific weight, the trend is towards finer fibres. Development of micro-fibre or nano-fibre media is made possible by means of sophisticated spinning and melt blown processes.

The fine nozzles, which are essential for the production of ultra-fine fibres are prevented from being blocked by particles or gels by melt filter systems and filters for spinning solutions.

Film production

There are three processes for film production depending on the polymer used. These are extrusion from the melt, stretching (mono- and biaxial) of a deformable solid, or casting of a polymer solution.

Casting is used with polymers that do not melt or which only melt under disintegration, like polyimides. Casting processes are also of interest for the production of ultra-thin films from thermoplastic polymers, like polyester or polycarbonates. Filtration is an essential step within film production to pre-treat melts or polymer solutions.

Depth filters retain undissolved polymers or gels from solutions, which would be detectable as specks within the cast film. These specks would significantly reduce the tear resistance of the films.

The production of ultra-thin films for challenging applications, e.g. in medical technology, is made possible by the high level of purity of the filtered melts and solutions.

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Membrane production

Most technical membranes for gas and liquid filtration with filter grades in the sub-micron and the molecular range are made from polymers.

Producing flat sheet membranes is quite similar to foil production, while hollow fibre membranes are made by spinning through a ring spinneret by means of a central air or water jet.

The chemical composition of the casting and spinning solution respectively, as well as the process parameters, influence the pore size distribution of the membrane.

Colloids or solid particles in the solution must be avoided in order to exclude membrane defects (like outsized pores) or embeddings that affect mechanical stability.

Leading membrane producers use Seebach filters for pre-treating polyethersulphon solutions prior to the production of ultrafiltration membranes.

Cable sheathing

Power cables are insulated by sheathing with plastics like polyethylene or polypropylene.

The higher the voltage and the more extreme the conditions surroundings of the cable, the higher the demands on stability and freedom of defects in the sheathing.

This is particularly true for submarine cables that connect offshore wind power turbines with each other or with the land. Again our melt filter systems ensure the highest purities of the melts prior to sheathing.

Production of polymer products

Polymer melts are used for the production of polymer products by injection moulding, and for the production of foils or fibres.

The melts can be classified on the basis of their viscosities and flow behaviour depending on the temperature, their chemical structure, and the level of polymerisation.

Melt filter systems ensure that polymer melts entering processing machines are free of particles and gels.

This prevents defects in the finished products. Seebach is the market leader in the design of customized and product-specific melt filter systems and their optimum adaption to existing production plants.

We produce filter candles, filter discs, and complete melt filter systems. Problems with gels are solved by specially adapted depth filter systems.

John Crane has first-class references in the field of high-performance polymers. Our Seebach product design and construction experts produce optimum filter systems without dead zones and lengthy dwell times.

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FREQUENTLY ASKED QUESTIONS

Common questions

What are industrial polymer solutions and how are they used in manufacturing?

Industrial polymer solutions refer to technologies used in polymer production and processing that help improve efficiency, product quality and equipment reliability. In polymer manufacturing environments, these solutions often include sealing systems and filtration technologies that support continuous operation, reduce contamination and maintain consistent melt quality in demanding processing conditions.

What types of polymer filters are used in industrial polymer processing?

Polymer filters used in industrial polymer solutions include systems such as melt filtration technologies, candle-style filter assemblies, continuous filtration systems and specialized filter elements designed for high-viscosity polymer streams. These polymer filter applications help remove contaminants and gels from polymer melts, improve product consistency and protect downstream equipment and polymer film processes.

Why are seals important in polymer processing industries?

Seals used in polymer processing industries play a critical role in maintaining system integrity, preventing leakage and ensuring safe, efficient operation of high-temperature and high-pressure equipment. Reliable sealing solutions help support continuous production, reduce downtime and protect rotating equipment in demanding polymer manufacturing environments.

How do sealing solutions support polymer filter performance?

Sealing systems are essential to the performance of polymer filtration equipment because they help maintain pressure integrity and prevent leaks in high-temperature melt environments. In systems that use polymer candle filters, melt filters or continuous filtration setups, robust sealing technology ensures consistent flow, minimizes contamination risk and supports long-term operational reliability.

What are common polymer filter applications in industrial environments?

Polymer filter applications are commonly found in plastic extrusion, fiber production, film manufacturing and resin processing. These applications require precise filtration of polymer melt streams to remove impurities and maintain product quality. In these environments, industrial polymer solutions often combine advanced filtration with high-performance sealing systems to optimize uptime and process efficiency.

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