How to improve surface finish in the infusion process

AME VPRO is an unreinforced barrier layer between gelcoat and laminate, is used primarily to improve the surface quality of rolled and water resistance as well as being effective against the marking fibers, is used primarily in the marine industry and especially for vacuum infusion.
Olli Piiroinen, European Manager of marine industry. Ashland Composite Polymers

AME VPRO is based on vinyl ester resins from Ashland base.

Features:

• Easy to apply, curing properties and resistance to sag.

• Can be used with standard MEKP peroxide-50.

• Low emissions.

• Versatile: can be used for any marine area, above or below the waterline.

• Excellent surface finish, profile enhancer.

• Superior chemical resistance.

• Cost efficient in production.

• Maintains flexibility integrally laminating and other physical properties.

Draft 16 months

Members:

• Ashland Finland - Resins.

• Ahlstrom Fiber Glass - Reinforcements.

• Mikpolis Ltd - Test facilities and instruments.

• Miktech Ltd - project planning, practical work and coordination.
Origin and objectives of the project

• Origin: the achieve good surface quality is considered the most important challenge of vacuum infusion. There is a need for a new test method for measuring the surface quality.

• Project Objectives: to develop a reliable test method for evaluating surface quality and achieve a good surface quality in the infusion.
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AME VPRO fully retains the flexibility of rolling and other physical properties.
Process and method

The testing process is divided into 3 stages:

- Development of a sandwich laminate test.

- Post-cured at high temperatures.

- Analysis of the laminate using a 3D profilometer. The 3D Optical Profilometer ago MicroProf optical measurements of surface profile, it calculates the parameters from any one area and create a 3D image of the surface.
Achieve good surface quality is considered the most important challenge of the vacuum infusion
The effect of curing

Vs. outdoor. Laboratory conditions:

• 16 hours post cure at 80 ° C is equivalent to one month outdoors under direct sunlight.

• The maximum external surface temperature of the laminate as about 60 ° C.
Reducing the set of fiber

• AME VPRO barrier layer above the 'skin coat' on surface quality.

• The addition of skin under the coat barrier layer does not significantly improve the surface quality.
Comparison of resins

• There are major differences between the resins in the final surface quality.

• unsaturated polyester resins were clearly the worst of the resins tested.

• DCPD resins and AME (VE) have similar surface characteristics.

• LP resins showed the best surface quality.
Laminate by infusion

The effect of resin chemistry on the surface quality:

• The chemistry of the resin has a very significant effect on surface quality.

• In infusion resins only low profile (LP) as such give a similar or higher surface quality compared to hand lay-up

• All traditional resins require the use of a coating that improves the surface (skin coat or barrier layer).

• The barrier layer (AME VPRO) improves the surface quality with better results than skin coat reinforced.

• When using traditional chemical resins, the best surface quality can be obtained with resin infusion low-styrene.

• Using low resin content of styrene DCPD results are improved surface quality when compared to ortho and isophthalic resins traditional.

• Of all the tests with no tracidionales resins LP, The AME 6000 INF (the next generation of vinyl ester resins low styrene content) are offering better surface quality.