JEC COMPOSITES MAGAZINE - Issue #140 - May/June 2021 - 55

GREEN-CHEMISTRY HONEYCOMB
Advanced Honeycomb Technologies (AHT) produces a
honeycomb product that combines an aramid core with low
fire smoke and toxicity (FST) characteristics with phenolic
resin, the material of choice for interior applications due to its
low FST.
Traditionally, phenolic resins have been solvent based. The most
common solvents used are ethanol, methanol,
isopropyl
alcohol, and acetone. These
solvents cause volatile organic compound
(VOC) emissions. For example, most of the
solvent-based phenolic resins for honeycomb production contain
35-40% ethanol, 35-40% isopropanol, and other mixtures. AHT's
use of water-based phenolic resin, as opposed to alcohol-based
solvents, eliminates most fire risks associated with honeycomb
manufacturing. Using a water-based resin also eliminates the
exposure of personnel to these solvents.The reduction or elimination
of volatile organic solvent emissions has provided new commercial
opportunities for the application of resins with low levels of volatile
organic compounds. Due to the reduced fire risk and the low
occupational safety risk of using water-based phenolic honeycombs,
the company enjoys the advantage of more sustainable production
than other counterparts using solvent-borne chemistry in the USA
and the EU. Producing honeycomb products with a water-based
phenolic thermosetting resin instead of a solvent-based resin is
clearly a significant benefit from an environmental point of view.
www.ahtinc.com
NEW INTERFACIAL BONDING
TECHNOLOGY FOR CFRP STRENGTH
F200 is a 121°C-curable epoxy
resin system that makes it possible
to achieve excellent compressive
performance of prepregs with
only a matrix change, without carbon
fibre treatment. Prepregs impregnated
with F200 show up to 45% improved
compressive
and
flexural
properties
compared to conventional prepregs.
This is a significant result of the
improved interfacial bonding technology
between the carbon fibre and the
matrix. The mechanical properties of prepregs, such as tensile, compressive,
flexural, shear, and fracture toughness, are very important for composite
material design. In general, it is possible to improve the flexural and shear
properties by adjusting the composition ratio of the matrix resin backbone.
As for compressive properties, it is very difficult to improve them with matrix
modifications only and improving interfacial bonding between the matrix and
carbon fibre has to be considered as well.
F200 has been tested by many companies in various fields, especially
for marine, bike frame, golf shaft and fishing rod applications.
Recently, a fishing rod company confirmed a strength improvement
of 20% for standard-modulus carbon fibre, 30% for intermediatemodulus
carbon fibre, and 45% for high-modulus carbon fibre.
www.hcarbon.com
LIQUID IMPACT MODIFIER FOR CFRP CAR WHEELS
Kane Ace™ MX, a liquid impact modifier based on core-shell rubber (CSR) technology, is utilized to improve the toughness and
fatigue resistance of mainly epoxy-based resin systems. These toughened systems are used in a wide range of applications
such as adhesives, composites, coatings, and electrical and electronic applications. In the automotive industry, there is
growing demand for carbon fibre-reinforced polymers (CFRP) in combination with epoxy-based resin systems. CFRP offer
great perspectives for weight reduction while providing additional advantages such as stiffness, toughness, and corrosion
resistance. Moreover, CFRP are increasingly used in more complex structures such as car wheels. Kaneka studied the toughening effect of CSR in
CFRP for car wheel applications. In order to demonstrate the efficacy of CSR, formulations based on cycloaliphatic epoxy resin with and without CSR
were studied and the company attempted producing car wheels with both systems. As Kane Ace™ MX has CSR pre-dispersed in primarily particles
(100-300nm) in the epoxy resin, no issue was found when being processed by RTM and the car wheel was successfully made. In this study, the car
wheel with CSR clearly showed superior performance in the 13° impact test according to AK-LH 08 and the rotating bending test, compared to the
wheel without CSR. This technology is also expected to be used for other CFRP parts. www.kaneka.be
INTERMEDIATES
HEXPLY® XF SURFACING PREPREG TECHNOLOGY
HexPly® XF technology is a surfacing prepreg that produces a superior surface finish for composite parts, with no pinholes or visible overlaps,
providing excellent out-of-mould surface quality that greatly reduces sanding and finishing operations, saving time and labour costs.
Developed to address the limitations of current wind turbine blade shell surfacing techniques whereby pinholes and other surface defects have to
be repaired by hand to achieve the perfectly smooth surface required for painting, HexPly XF increases overall blade manufacturing efficiency by
reducing time in the mould by up to two hours and by banishing surface defects that require rework before painting.
This lightweight, easy-to-handle, non-woven semi-preg material is supplied in roll form that can be co-cured with standard
epoxy infusion systems or used in prepreg production processes. After curing, the component is de-moulded with the
manufacturer benefitting from a pinhole-free surface that needs minimal preparation before painting. The material is less
than half the weight of a typical gelcoat per square metre, reducing the overall weight of the blade.
The consistent areal weight and thickness of the prepreg film provide a completely uniform surface coating, ensuring
blade weight distribution and balance are maintained. With no need to handle or mix liquid chemicals as in the gelcoat
process, HexPly® XF also improves the health and safety working conditions on the shop floor. www.hexcel.com
No133 March - April 2020 / jec composites magazine
55
Wind energy
Automotive
Multi-sector
Multi-sector

http://www.ahtinc.com http://www.hcarbon.com http://www.kaneka.be http://www.hexcel.com

JEC COMPOSITES MAGAZINE - Issue #140 - May/June 2021

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #140 - May/June 2021