A brief difference of the four Plastics used in the boating industry.

The boat price difference found on the market is a result  of the plastics used in the building proces.

To start with the cheapest of the 4 plastics used is: Ortho-Polyester resin, it only elongates 2% before cracking with a tensile strength of 65mPa.
This results in the Plastic cracking before the Glass reinforcement fibers reach their usefull working strength.

Next is the Isophthalic-Polyester wich streches about 2.5% and about the same tensile strength, but has a better chemical resistance (degradation by oil polutants).

During the last 10 years the yachting industry started using a slightly more expensive better resin being Vinylester-resin.
This Vinylester-resin has twice the elongation of Polyesters and a tensile strength of about 85mPa , this means the bond between the layers of glass is better.
Vinilester-resin has a higher chemical resistance compared with the other polyesters and is less hygroscopic.

The strongest of all is the Epoxy-resin with an elongation of over 5% and a tensile strength of 86mPa, it has a higher chemical resistance than Vinylester and is water proof.
A core material combined with a glass mat can be stronger than Stainless steel .
The price of Epoxy-resin is the most expensive of all and follows the higher oil prices now a days.

Read more about Fiberglass.

Epoxy Composite Construction

Twenty-five years of advances in construction techniques using epoxy-bonded materials have revolutionized boatbuilding and set new standards for performance and reliability. Leading builders are building stronger, lighter, more durable boats with epoxy composite construction.


THE EVOLUTION OF BOAT CONSTRUCTION
For centuries, artisans shaped, fitted and assembled timber into wooden boats. Builders developed sophisticated wood construction methods, but never overcame wood's susceptibility to rot and significant maintenance requirements. The development of fiber reinforced plastics (FRP) offered apparent solutions in new materials and techniques. The explosive growth of fiberglass-polyester boats over the last thirty years was built on the perception of low maintenance and easy fabrication. However, as with wood, polyester resins have been plagued by the effects of moisture penetration. The problems of rot and softening were replaced by hydrolysis, blisters and delamination. The solution to these problems lies in epoxy composite construction.


WHAT IS EPOXY COMPOSITE CONSTRUCTION?
Epoxy composite construction consists of bonding all of the materials and parts of the boat together with epoxy resin. The resulting structure has physical characteristics superior to the components by themselves. Composite construction includes a variety of building methods that use epoxy to protect the materials from moisture as well as hold the materials together. Epoxy resins, the key ingredient, are among the most versatile of thermoset plastics. They bond exceptionally well to a wide range of materials and are highly moisture resistant. Compared to polyester resins typically used in fiberglass boat construction, epoxies have greater strength, less shrinkage, better moisture resistance and better fatigue resistance.



A NEW INTEGRATED MATERIALS TECHNOLOGY
Combining the best of wood technology with the advances in FRP materials and processes, leading builders have turned to composite construction to produce durable, distinctive boats. Builders use the moisture resistant qualities of epoxy to take advantage of wood's strength, stiffness, light weight, resistance to fatigue, insulating ability, availability, cost, and beauty. Epoxy's excellent adhesion to balsa and plastic foam cores, glass, aramid and carbon fabrics, allows the builder the advantage of selectively integrating these materials into the boat's structure. Designers, builders and owners have more choices available. Through epoxy composite construction, the builder can offer boats in a wide range of designs, materials and construction methods.


WHAT ARE THE ADVANTAGES OF EPOXY COMPOSITE CONSTRUCTION?

Versatility
The builder using composite technology can build boats with a range of materials, designs, and construction methods that are perfectly suited to the boat's use and the customer's needs. Everything from strip canoes to work boats, high performance multihulls to offshore racing powerboats have been built using epoxy composite construction. Composites can be uncomplicated structures of wood and wood veneer or complex vacuum laminated hybrids incorporating glass fabrics, aramid, or carbon fibers.

Lower Maintenance
All of the components in a composite boat are protected by an epoxy moisture barrier. Since the moisture content is stabilized, the maintenance problems associated with wooden boats - rot, joint cracks, structural members swelling or shrinking, and surface checking - are eliminated. Epoxy provides a stable base for paints and varnishes, reducing the frequency of refinishing. In glass laminated boats, epoxy's superiority to polyester resisn as a stable moisture resistant adhesive reduces the possiblility of delamination and gelcoat blistering caused by moisture penetration.

A History of Success
Epoxy composite construction techniques for boatbuilding were first developed over thirty years ago. Over the years, thousands of composite recreational and working boats have been built and the earliest are still going strong. Composite construction has proved itself at the top levels of competition in sail and powerboat racing, in the harshest environments and under the toughest working conditions. Epoxy composite boats have set a standard for performance, reliability and beauty.