In today's rapidly evolving industrial landscape, businesses are under increasing pressure to invest in innovative technologies to meet market demands. At the recent SABIC Conference, we had the honor to present insights on how machine design is transforming the foam industry to meet pressing market demands like sustainability, cost efficiency, and product innovation.
However, companies face significant hurdles, including higher labor costs, volatile raw material prices, and fluctuating energy costs, all of which squeeze profit margins. At FAP, we embrace these challenges head-on, focusing on how extrusion machinery is evolving to meet the demands of today and tomorrow. Let’s dive into the world of polymer foams, the challenges they present, and the cutting-edge solutions we’ve developed.
Polymer foams have been indispensable in various applications for years, from acoustic and thermal insulation to food packaging. Imagine enjoying authentic Italian gelato stored in an XPS foamed container - an everyday example of how foams enhance quality of life. These versatile materials are made primarily from polymers like PP, PE, and PS, using physical expansion (with CO2) or chemical expansion methods to achieve their unique properties.
The global push toward sustainability demands recyclable products. While physical foaming offers this advantage, chemical foaming renders products non-recyclable. The market already favors recyclable solutions, and soon, clear labeling will classify products as "green" (recyclable) or "red" (non-recyclable).
But the journey to sustainability isn't without challenges. Incorporating recycled materials into production introduces variability in material properties, leading to uneven density, foam collapse, and increased waste. Dispersion of recycled granules and gases within the melt remains a critical hurdle.
Market pressures often lead clients to ask: “Can you lower your price per square meter?” With labor costs fixed, the focus shifts to reducing material and operating costs. Traditional extrusion processes lack precise energy monitoring, and inefficiencies during startup or material change increase expenses.
At FAP, we are dreamers - and our mission is to turn dreams into reality. Our innovative extrusion technologies empower companies to achieve their goals by addressing these challenges with tailored solutions.
For those who choose the second path, FAP offers groundbreaking solutions.
Our twin-screw counter-rotating extruders redefine material homogenization. The counterrotation creates dual mechanical shear stresses, ensuring uniform dispersion of additives and gas. This process enhances foam cell formation, delivering products with superior physical properties.
By applying high pressure to molten polymers, we increase gas solubility, achieving recyclable foams with exceptional thermal stability, compressive strength, and low density. These properties rival those of traditionally non-recyclable, chemically foamed products.
Flexibility is key in today’s market. FAP technology enables clients to produce foam thicknesses ranging from 0.3 mm to 25 mm using the same machine. Additionally, our extruders support diverse polymer compositions (e.g., PP+EVA, LDPE+MLLDPE), offering unparalleled adaptability to market demands.
Our commitment to innovation is embodied in the Italian Foam Centre for Research & Innovation, where we explore new materials and optimize processes to push the boundaries of foam technology.
Packaging is critical in foam production, ensuring product quality during transport. In the 1990s, we revolutionized the process with our Soft Winder system, which:
This innovation has cut raw material costs by 6% per square meter, delivering both quality and cost-efficiency.
For foam thicknesses above 8 mm, we have achieved the use of 100% recycled PIR material without any virgin resin. Our clients integrate up to 30% PCR content using highly selected and filtered scraps, further advancing sustainability.
Our "smart" cooling systems and advanced thermoregulation reduce startup times by up to 60 minutes and process waste by 30%, saving up to € 400 per startup. Pressure control across screw sections enhances energy efficiency, lowering energy consumption by 44% compared to traditional systems.
At FAP, we don’t see problems - only challenges waiting for solutions. Our commitment to innovation ensures that what once seemed like a dream becomes reality. From 100% recyclable foams to cost-effective, high-performance machinery, we are transforming the foam industry.
If you share our vision for a sustainable, productive future, let’s start a partnership. Together, we can turn dreams into reality.
Contact us or visit our R&D center to discover how FAP can empower your business.
Extruded polystyrene (EPS) foam is today the main and cheapest type of foam polymer from which most single-use food containers and trays, coffee cups and egg containers are made.
So why are there more and more companies choosing the production of expanded polypropylene (EPP) in recent years? There are many debates, discussions and articles on this topic, and in some countries the use of extruded polystyrene foam in food packaging is already completely prohibited by law or is going to be soon.
Modern technologies make possible to recycle and reuse both polypropylene and polystyrene, but there is always a "BUT".
And here are some of notes about the properties of EPS foams:
The use of recycled polystyrene, as opposed to recycled polypropylene, is much more limited. Recycled polypropylene can be used in many industries, from injection molding to polypropylene filament production with varying percentages depending on the industry.
EPS foam is significantly inferior to EPP foam in terms of resistance to high temperatures. Thus, disposable tableware made of EPP foam can be used at temperatures up to 120-130 °C, and tableware made of EPS foam cannot be used at temperatures above 80-90 °C.
If we look at the statistics of the total volume of plastic waste recycling, polystyrene recycling takes up on average 9% of the total volume of recycled waste of this type of raw material, and the share of polypropylene recycling in the total volume of its disposal to landfill is on average 17%.
In addition, due to the more costly sorting process, more expensive logistics to recycling centers and the peculiarities of processing this type of waste, more and more factories are refusing to process expanded polystyrene.
This is pushing governments around the world to ban the use of extruded polystyrene in the food industry. Even though it is a single use, food container in EPP is not going to be banned and it will be a valid and safe alternative and totally recyclable solution worlwide.
Our ITALIAN FOAM CENTRE, together with polyolefin manufacturers and partners, is working to find opportunities and give new and improved physical and mechanical characteristics to polypropylene foam, making this product even more environmentally friendly and accessible to the market.
After a year of informal activities setting the groundwork, WIP-IT is now formally constituted, complete with its own Statute, Manifesto, Code of Conduct, and Regulations. This new structure brings together entrepreneurs, employees, managers, and freelancers, all dedicated to fostering positive change in an industry traditionally dominated by male presence.
Association Goals
WIP-IT’s mission focuses on promoting inclusivity and social and environmental sustainability within the industry. The association aims to enhance the image of plastic materials through their sustainable uses and to develop a strong network of support and collaboration among female professionals. WIP-IT's values and principles are designed to have a significant impact on the cultural, social, and environmental framework of the plastics sector.
First Assembly: Participation, Elections, and Future Goals
The first assembly was held in Cremona on October 29, 2024, with over 50 new members joining the event, eager to share the association’s vision. During the assembly, the new positions were elected for the next term (until 2028):
The assembly also presented an overview of the projects completed over the past year and laid out plans for the future. The focus will be on education and training initiatives through events and courses, aimed at building skills and awareness among members. Key topics will include sustainable innovation in plastic materials and best practices for use and recycling.
Commitment to Inclusivity and Social Impact
Membership is open to individuals, as well as companies and organizations, who can participate as supporting or affiliated members. Member companies commit to fostering an inclusive work environment, ensuring equal opportunities, and supporting work-life balance for their employees.
The next Women in Plastics Italy event is scheduled for May 2025, coinciding with the Greenplast trade fair.
Let's figure it out together.
The cost of raw materials in calculating the full cost of 1 m2 (1 ft2) of the product can reach 55% and, undoubtedly, reducing the weight of the product even by 10% can save serious amounts of money. But at the same time, how can we avoid ultimately getting an increase in technological defects associated with collapse, cell rupture, a decrease in the physical and mechanical properties of resistance to loads, etc. when reducing the density of physically polyethylene foam (EPE)? In addition, the question arises, what is the minimum density of the finished polyethylene foam product that we can obtain in the extrusion process so as not to have problems with quality later? Can we be sure that after a week of keeping the products in the warehouse we will not have to dispose of and granulate the entire batch or, even worse, pick up this defective batch of products from the customer's warehouse?
At FAP, we have recently been regularly faced with requests such as: "I need to produce polyethylene foam with a density of 12 kg/m3 (0,75 lb/ft3), but I must be sure of the quality. Can your foam extrusion lines do this?" or more "I saw non-crosslinked PE foam material with a density of less than 14 kg/m3 (0,87 lb/ft3) at the exhibitions, it was recommended a production line, and I bought it! But for some reason I cannot produce such a product. Could your process engineer come and set up our new line to produce a product with a density of at least 13 kg/m3 (0,8 lb/ft3)?"
How to calculate the gas saturation coefficient of molten polymer and why it is impossible to cheat the laws of physics. Where is the limit of density reduction of physically foamed polyethylene and why most of the information on the market has nothing to do with REALITY.
Let us remind you that we are talking exclusively about foaming polyethylene, polypropylene or polystyrene by extrusion and the solubility of liquefied hydrocarbon gases in them under pressure.
Yes, of course, various tests were carried out, such as obtaining physically foamed ultra-low density polypropylene in the range of 10 kg/m3 (0,62 lb/ft3) by one of the largest manufacturers of foamed polyethylene in the world, but these tests did not find industrial application, since the process is simply impossible to control on an industrial scale.
It is no secret that the low density of physically foamed polyethylene is achieved by solubility in the melt of the largest amount of foaming agent, in our case, a gas such as Butane. The higher the viscosity of the gas and the greater its volume retained in the liquid state inside the extruder, the better the gas is dispersed into the melt and a smaller volume of it evaporates when the polymer exits the foam extrusion head (foam extrusion die).
During the extrusion of low-density polyethylene, the melt temperature in the extruder reaches 160-180 °C (320-356 °F) degrees and at this temperature it is necessary to maintain a minimum melt pressure (above 50 bar) so that butane has sufficient viscosity in the "borderline" state in order to mix with the polymer melt.
The technology of twin-screw extrusion with counter-rotation from FAP is capable of maintaining such a high melt pressure regardless of the pressure in the foam extruder head (foam extrusion die) and that is why this technology, unlike the most common single-screw extrusion on the market, is capable of producing both very thin foams with a thickness of 0.3-0.5 mm (1/64-1/50'') and foams with a thickness of 25-30 (1-1,2'') mm on the single line.
But even the counter-rotating twin-screw extrusion technology from FAP, which is the best technology for physically foamed polymers today, has a limit in the volume of gas dissolved in the polymer and, accordingly, the weight and density of the finished foam product. For example, the % solubility of gas in the production of physically foamed polyethylene with a thickness of 2 mm (1/12''), a width of 2 m (6,6 ft) and a density of 15 kg / m3 (0,94 lb/ft3) in the extrusion process using a FAP twin-screw extrusion line is 4-4.5% of the polymer volume and is the maximum indicator. That is, if we take the volume of the polymer mass of 250 kg / hour in the extrusion process, we can dissolve in it only 10-11 kg of liquefied butane, taking into account the polymer processing temperature and the melt pressure both in the extruder and in the extrusion head. The rest of the introduced volume will evaporate during the foaming of the polymer with a sharp drop in pressure. Increasing the solubility of gas in the melt is complicated by the fact that it is necessary to both reduce the melt temperature to increase the viscosity of the gas and significantly increase the melt pressure.
But when the melt temperature is reduced to increase the viscosity of the gas, the viscosity of the polymer also increases, making it difficult to disperse the gas, and in the case of increasing the temperature to reduce the viscosity of the polymer melt, even with an increase in the melt pressure, we increase the time for the crystallization of the polymer after foaming and thus the foam loses more gas during evaporation, which leads to partial collapse.
The second limitation is that with such a low density of foam plastic, the walls and edges of the cells are very thin and, accordingly, the risk of shrinkage, collapse of the foam plastic, or rupture of the cells during gas expansion is very high and is almost 100%. Such a low density is not a problem for open-cell foam plastics such as polyurethane, since there is not such a high pressure difference in the cells as in closed-cell foams. If we consider foamed polyethylene with a density of 12 kg/m3 (0,75 lb/ft3) during production, we will see that the foaming coefficient is 77.08, and the volume of the polymer itself per 1 m3 of foam (finished product) will be only 1.297%. As you understand, these figures are on the verge of fantasy.
But how do we come across such light samples of physically closed-cell polyethylene foam at exhibitions? Today, more and more manufacturers declare such figures, misleading manufacturers. In fact, there is nothing unusual. As manufacturers, we measure the density during the production process, at the moment when the material is produced on the production extrusion line. But how does the density of foamed polyethylene change after the full degassing period, that is, when the butane inside each cell is replaced by air.
For visual calculations, let's take the same material of polyethylene foam with a thickness of 2 mm (1/12'') x a width of 2 m (6,6 ft) x a density of 15 kg / m3 (0,94 lb/ft3):
- The weight of one square meter of our material during the production process will be 31.8 grams,
- Based on the density of the dissolved gas and the warehouse temperature of + 15 °C degrees (59 °F), the weight of gas in 1 m2 (10,7 ft2) of material will be 4.05 grams,
- In the process of replacing gas with air for about 19-25 days, our 1 m2 (10,7 ft2) of foamed polyethylene will lose about 3.3 grams in weight, since the specific volume of air m3 / kg is 5.66 times higher than that of butane,
- As a result, after 19-25 days, 1 m2 (10,7 ft2) of our material will weigh approximately 28.5 grams, which is 10.4% lighter, and the density of this material will be 13.4 kg/m3 (0,8365 lb/ft3),
- And if we take the time for the gas to escape over 40-50 days, then the weight of our sample will change by as much as 14.5-16 % and, accordingly, the density will decrease and approach 12 kg/m3 (0,75 lb/ft3).
Thus, it is important to distinguish the time of measurements of the finished foam product and understand when these measurements were made.
The process of gas substitution with air in closed cell foam with liquefied hydrocarbon gases (degassing process) is one of the most important processes, which is at the same time a "bottleneck" in the foam polymers productions. The degassing time of the foamed polymer directly affects both the final cost of the finished product and the manufacturer's responsiveness to customer orders, which is a very serious advantage in these highly competitive times.
Glycerol monostearate GMS - belongs to esters, migrates to the foam surface, reducing friction and static charges on the foam surface. Like all migrating antistatic agents, GMS accumulates moisture on the foam surface and creates a very thin greasy layer. The quality and the amount of GMS required in the formulation can significantly affect the air permeability into the polymer and increase degassing time by 10 - 15% depending on the amount introduced.
It's very important to maintain optimal temperature and humidity in the warehouse. For example, at a warehouse temperature of +25 °C the volume of air migration into physically foamed PE is on average 0,0030 grams/m2 per hour, while at a temperature of +5 °C this figure can be reduced to 0,0015 grams/m2 per hour. In southern countries with humid climates, the degassing process is usually faster, but it also often leads to rupture and collapse of the gas structural element.
Unfortunately, there is no complete understanding of how important correct winding technology is in foam productions. In the process of winding roll, it is important to ensure that the foam tension does not depend on the diameter of the roll and that the core of the roll is not compressed. This is a very big problem for simple type winders. For this reason, each FAP winder is equipped with the so-called "Soft Winding System". This is a smart winding system that controls the equal tension of the winding rod for each running meter of material without creating a tightening effect on the core of the roll.
The creation of a small air gap between each wound meter of foam material allows to achieve a gas exchange air permeability of 0,0023 grams/m2 per hour even in the core of the roll, which is on average 0,0009 grams/m2 per hour more or 39% more than without "Soft Winding System" (calculations done at a temperature of +18 °C).
At FAP, we understand that the extrusion of gas-filled polymers is a critical process requiring precision and the right equipment. However, the lamination of physically foamed materials is equally important. This process involves bonding foamed polymers either to themselves (to increase thickness) or to other materials like reflective foil, PET, and HDPE, enhancing the final product's physical and mechanical properties.
Though lamination might seem simple, it has many nuances that can affect the final product's quality, productivity, workplace safety, and production costs. What technical features of the equipment can be both an advantage and a significant drawback? Here’s what manufacturers and / or "converters" should consider when selecting equipment for laminating physically foamed polymers and bubble wrap:
For nearly four decades, FAP’s closed-cell foam polymer lamination technology has been trusted in Europe, North, and South America. Continuous improvement by our team of engineers and technologists, combined with a deep understanding of critical processes like "degassing" of physically foamed polymers and adhesion changes under complex esters and antistatic agents, allows us to create unique and high-quality lamination lines.
FAP is a dynamic second-generation family-run company with over 37 years of international experience in the design and construction of foam machinery and R&D activity to create for our customers something truly valuable and capable of raising the production of foamed polymers to a completely different level.
In this regard, Borealis and FAP set out to make low-density EPP foam applications that are more easily recyclable. The performance properties that have ensured the popularity of polymer foams would have to be maintained – or even improved. By leveraging their expertise in polypropylene resins and foaming technology, respectively, the partners aimed to improve physical foaming processes in order to offer innovative material solutions that are affordable, resource efficient, and more environmentally compatible.
Nowadays, the technology of extrusion of physically foamed branched polypropylene, which is still little known to the markets, is of great interest. Light weight, strong, thermoformable, 100% recyclable with excellent insulation properties. These and other characteristics have made it the unique material that can replace most traditional polymer materials in markets such as insulation in the automotive industry, heat and sound insulation in construction, and the food industry.
By leveraging the wide-ranging expertise in PP foaming technology, we improve physical foaming processes in order to offer innovative material solutions that are affordable, resource efficient, and more environmentally compatible.
Extrusion has been recognized as the most common foaming technology. Branched PP is a crystalline material with high melt strength compared to low-density PE and has technological differences in production.
Production of ultra-low physically foamed polypropylene (<25 kg/m3) and thickness from 1 to 10 mm with high quality characteristics is possible exclusively with a hydrocarbon foaming agent (such as isobutane or n-butane) and using twin-screw foam extrusion technology, which will create a certain pressure and melt speed to dissolve gas into the polymer even at high temperatures melting required for polypropylene processing. Inert gases can also be used in extrusion foaming, like supercritical nitrogen (N2) or carbon dioxide (CO2) for production of higher density foams of 150 kg/m3 or more. Non-combustible CO2 reduces the industrial hazard class in the physical foaming process, it is easier to store, and fairly inexpensive.
In contrast to conventional PP, WB140HMS offers a combination of high melt strength and low melt viscosity due to the shear thinning effect caused by the branch structure. Its excellent foamability and consistency are complemented by its easy processing. This further enhances the efficiency of the closed-loop production of PP foam: all material waste generated during production is immediately turned back into granules and fed back into the process, thereby reducing the use of virgin raw materials – with no compromise in mechanical performance.
Having tested the use of CO2 as a foaming agent in the laboratory for many years, FAP was able to develop a new machine to foam EPP using CO2, where the screws are designed in such a way as to maintain the necessary pressure in the gas injection zone at high temperatures. Further tests led to the development of a unique extrusion head and dies allowing to obtain high quality cellular structure of the foam and much better control over the expansion and crystallization of the polymer after leaving the extrusion head.
To find it out, we have to consider: administrative costs; production costs; warehouse costs.
In this article, we will consider production costs, specifically those costs necessary to produce final products from expanded polyethylene (EPE) and polypropylene (EPP) foam.
1. Raw materials (usually represent 45-55% of the total cost of finished products)
2. Logistics (warehouse and storage)
3. Energy costs
4. Work productivity indicator
The polyethylene (EPE) and polypropylene (EPP) foam processing sector is slowing down; some, even speak of oversaturation of the offer. To overcome this problem, manufacturers have often chosen to act on quality by: reducing product density, reducing nominal thickness, choosing low-cost raw materials. This strategy has enabled them to survive in the short run but cannot be considered a solution.
A key factor in the overall calculation of production costs for expanded materials such as polyethylene foam (EPE) and polypropylene foam (EPP) is the choice of equipment and process technology.
Using low-cost technology may seem convenient, until we quantify how much it costs a company to produce 1 sqm of defective product.
In order to provide a technological advantage in production, FAP engineers design our lines with 4 fundamental characteristics:
Equipped exclusively with independent gravimetric dosing units with a dosing accuracy of 0.3%, for the best control of the recipe (for checking the cost of raw materials per unit of product). The station is able to guarantee the change of any component during the production process in 7 minutes max. (for the minimization of production waste).
Reducing production waste allows reducing inventories, increase stock turnover and obtain cost-effective batches, thus reducing product storage costs.
The twin-screw counter-rotating FAP foam technology significantly reduces:
- the risks of foam shrinkage due to the disruption of its cellular structure;
- bubbles on the foam material due to thinning of the cell walls;
- excessive gas expansion.
This eliminates the risk of products "overproduction", which would also affect their storage costs.
The cost of energy is rising: in many countries, in recent years, it has doubled. It is evident that this item has a great influence on production costs. This is why FAP complies with the highest and strictest energy efficiency standards by designing with specific attention:
- the heating elements: FAP extruders are shorter and more compact than single-screw extruders and consume 25-30% less electricity to heat the cylinder;
- the main motor: ABB's unique SynRM jet-rotor motors with energy class IE5 provide high specific power and torque and low winding and bearing temperatures, thus reducing energy consumption by 25-30% compared to standard induction motors;
- the gearbox: the modern Zambello ZT3 gearbox guarantees a high transmitted torque density (up to 17 Nm/cm3 per shaft).
FAP foam extrusion lines are some of the most efficient in terms of energy consumption per unit of production and provide huge cost savings.
Industrial automation processes are more important today than ever before: production lines must be intuitive in order to simplify the training of operators and quickly train new ones, but they must also be able to independently (automatically) perform numerous technological tasks.
By minimizing the number of operations on the line performed directly by operators, it is possible to significantly increase labor productivity in production, thus positively influencing the cost of finished products.
Due to the annual increase in logistics costs, the company was no longer able to purchase high-quality foil and metallized BOPP film from the European Union. Since the company was very focused on the production of polyethylene (EPE) and polypropylene (EPP) foam insulation with metallized BOPP film sheet lamination, it was imperative to find alternative materials and the only one supply option was China. The main problem was that the thickness of the cast polymer layer of BOPP film and aluminum foil was 2.5 times thinner than before. Chinese suppliers simply did not want to produce material exclusively for our customer's needs, since the volumes were not enough.
In this regard, our client asked us for support in developing new technological processes associated with the production of laminated thermal insulation from polyethylene and polypropylene foam in order to minimize the risks of foil and metallized film peeling off polymer foam after lamination.
We understood that simply changing lamination technological parameters would not help in this situation, since the problem lies solely in the quality and characteristics of the foil and metallized film used.
It was decided to work on increasing the adhesion of foam to foil and metallized film, as well as slightly change the recipe of the raw materials of the extrusion process in order to increase the gas permeability of the foam polymer and reduce the amount of residual gas in the cells of the foam polymer during the lamination process.
Firstly, we conducted an audit of technological processes, the raw materials and additives used.
The actual degassing period of the material was determined by observing changes in weight, density, and expansion of the material over several weeks at various temperatures and other conditions.
It has also been established that the quality department does not pay attention to the actual time of degassing of finished products and semifinished products and that EPE and EPP foam are often used before the actual time of replacement of gas with air, which also affects the formation of defects during lamination, since there is a large amount of residual gas during the heating process, expands between layers and prevents adhesion between films and foam.
Another feature of this project was revealed, that the customer could not afford to increase the current degassing period of foam materials due to limited storage space.
We drew up a plan for modifying the recipe with calculations of costs. It was planned to replace the standard GMS lubricant with another sliding additive in order to increase gas permeability and reduce the degassing time to no more than 10 days. It was also decided to introduce a polar copolymer of ethylene and butyl acrylate into the formulation of foamed polymers to increase the adhesion of foam materials when heated during the lamination process.
FAP teams completely took over the process of searching for suppliers of raw materials, carried out a regulated process of testing and introducing new types of raw materials into the recipe. Training materials were also prepared in the form of presentations for operators, technicians and the quality department managers, which contained detailed theoretical material on the foaming process and the influence of existing and new types of raw materials on the process. A meeting and training of all personnel was organized for 1 working day with production stopped.
By introducing new raw materials into the recipe, it was possible to bring the degassing period of foam closer to 11 days, which satisfied the customer.
In addition, the introduction of a polar copolymer increased the adhesion of foam during lamination, since the initial melting temperature of the copolymer is 12 degrees lower than the melting temperature of low-density polyethylene.
Incorporating a small percentage of this material into the formulation created a more sticky layer on the surface of the foam when heated, but the production cost of the foam polymer increased slightly. Because the film's polymer coating layer was thinner, the current cost of purchasing metallized BOPP film and aluminum foil was significantly lower than before, about 40%, making the final product more economical despite the formulation changes.
FAP Srl is a member of AMAPLAST Italian Plastics and Rubber processing machinery and
moulds manufacturers’ association.
