Ultra-High-Molecular-Weight Polyethylene is nowadays a fibre well known in the sailing industry. People know it through its well-known commercial brand, Dyneema. We are proud to be one of the first to use it in string sails, back in 2013, achieving good results from the very beginning. Today, it is largely used at Powerplast because of its unique properties.

It is important to know that there are several types of UHMWPE available on the market, each with different mechanical properties. Currently, we are using Dyneema fibres from DSM, specifically the SK99 and SK78 types. These two types share the same excellent resistance to UV radiation and chemical substances, as well as low creep and low specific density. These fibres are so light that they can float on water.

A well-known fibre in the sailing industry, carbon is one of the best materials available in terms of overall Elastic Modulus. In this field, the preferred option is medium modulus carbon, with a modulus of 240 GPa. This choice balances the high elasticity of carbon with its inherent fragility: the higher the rigidity, the more brittle the fibre.

Carbon has a tenacity of 26 cN/dtex and an exceptionally low elongation at break of 0.8%.

It is available in 1800 dtex (3K) and 3600 dtex (6K).

Para-aramid fibres are man-made fibres with outstanding mechanical properties. At Powerplast, our preferred brands are Twaron and Technora.

Twaron

Twaron is the brand name for para-aramid fibres produced by Teijin, a globally renowned fibre manufacturer. It is comparable to Kevlar by DuPont. At Powerplast, we select Black and Gold Twaron HM (High Modulus) for its versatility, as it integrates seamlessly with other high-performance fibres such as Carbon or Dyneema.

Twaron HM has a high Young’s Modulus of 104 GPa, providing excellent stiffness, combined with a tenacity of 25 cN/dtex. It offers low elongation at break, measured at just 2.8%. The fibre exhibits good resistance to chemical substances, although it is sensitive to exposure to acids (pH < 2) and bases (pH > 10). UV radiation can weaken Twaron’s strength, but the black-pigmented version is more UV-resistant compared to the natural gold Twaron. Its specific density is 1.44.

Twaron is available in 1200 dtex, 1600 dtex, 2800 dtex, and 3200 dtex, making it suitable for a wide range of applications.

Technora

Technora is the brand name for another para-aramid fibre produced by Teijin, distinguished from Twaron by two key characteristics: Elastic Modulus and flexural resistance. Technora is available as a standard modulus fibre with an Elastic Modulus of 74 GPa, a tenacity of 25 cN/dtex, and an elongation at break of 4.4%. It is less rigid than Twaron HM and shares the same sensitivity to chemical substances and UV rays.

However, Technora offers better performance in flexural fatigue. While Twaron’s performance in this area is already high for sailing applications, Technora provides even greater durability under repeated bending. That said, flexural fatigue is typically measured in millions of cycles, which are rarely encountered in normal sailing conditions.

The specific density of Technora is 1.39, making it slightly lighter than Twaron.

Technora is available in 1200 dtex and 1600 dtex, offering versatility for various applications.

Liquid Crystal Polymers (LCPs), with Vectran being the most well-known, can serve as a viable alternative to UHMWPE, but only when used in its Ultra Modulus form. This type of LCP is still not widely available, and we are actively researching its potential for our applications.

Polyester fibres are used in sailing industry since ’50. At Powerplast we keep this fibre only for boats where the use of this fibre is compulsory. We think that when we build a string sail, the production cost of using a cheaper fibre is not changing much, so we prefer to deliver to our customer a better product at the same price. Polyester has good UV and chemical resistance, Elastic Modulus of 17 Gpa and tenacity 8.0 CN/dtex and a breaking load of 14%. Clearly it is not the best material for having a light sail performing at best. Specific density is 1.38%.

We are really proud of the skins’quality level reached at Powerplast. Since the beginning, back in 2010, we invested a lot of time in searching for new materials suitable for membrane skins. Today we have a full list of skin materials designed and produced by us or for us.

Our bi-axially oriented Mylar film is available in two thicknesses, 19 microns and 23 microns. Mylar, a commercial name for PET, is known for its strong mechanical properties, particularly its excellent bias stability. Transparent in nature, Mylar with an added thermoplastic glue weighs 62 g/m² or 72 g/m², depending on the thickness. However, Mylar is difficult to glue and offers limited UV protection for fibres, resulting in reduced durability. As a result, it is primarily used in conjunction with another layer of Mylar film.

This non-woven textile, made from polyester fibres sourced from the aeronautical industry, exhibits orthotropic behaviour, achieving greater tensile strength than Mylar. It features Powerplast’s unique coated resin, developed for all Filmless products. This resin provides UV-blocking and anti-mildew treatment. Filmless Light has a weight of 70 g/m² and is available in a melange grey colour. Its reliability in rolling applications and softness compared to Mylar, combined with excellent lamination strength, result in increased durability. It can be applied to Filmless Fusione.

This lightweight polyester taffeta significantly enhances the mechanical performance of Filmless Light, doubling stiffness, strength, and bias orientation stability. It incorporates Powerplast’s specialised resin, which is UV-blocking and mildew-resistant. Filmless Light 2.0 weighs 68 g/m² and is available in black, white, and shark grey. Its improved lamination strength and tenfold increase in abrasion resistance set a new benchmark for high-end sails. It can be applied to Filmless Fusione and Filmless Standard.

This polyester taffeta skin is the foundational component of Filmless Original, well-regarded for its durability and shape stability. It features Powerplast’s unique UV-blocking and anti-mildew resin. Filmless Standard weighs 105 g/m² and offers outstanding lamination strength with excellent durability and shape retention. Its bias performance matches that of Mylar products of the same weight. It effectively protects reinforcement fibres from UV damage, with two layers reducing UV harm by 95%. It can be used with Filmless Light 2.0, Filmless Fusione, and Filmless Heavy Duty.

Designed as the base component of Filmless Storm, this polyester taffeta skin enhances abrasion and tear resistance by 50% and tensile strength by 20%, compared to Filmless Standard. It incorporates the same Powerplast resin, which is UV-blocking and mildew-resistant. Weighing 125 g/m², it offers the same lamination performance as Filmless Standard while providing superior fibre protection. It is compatible with Filmless Standard.

This low-carbon-footprint version of Filmless Standard is made with recycled polyester fibres derived from plastic fishing nets recovered from oceans and plastic bottles. It uses the same resin as other Filmless products, with tensile strength just 5% lower than Filmless Standard.

Carbon Nanotube added Polyurethane film created by Powerplast. This product is the result of research project of Politecnico di Milano sponsored by Powerplast. We started from a known Polyurethane film that we were using, having really good adhesion properties. However, this material was too fragile to be used on its own, so we decided to improve its mechanical performances adding Carbon Nanotubes. Carbon Nanotubes are sheet of Carbon molecules, arranged in cylindrical shape, that can enhance mechanical and electrical properties of many materials. Adding them to our base Polyurethane, we increased its mechanical properties by 40% and its tribological properties has been improved by 10 times.