2024年6月13日发(作者：柳俏丽)
HIGHER TG RECYCLABLE HIGH PRESSURE RESIN TRANSFER
MOLDING (HP-RTM) EPOXY PROPERTIES AND HOW THEY
COMPARE TO A COMMERCIAL SYSTEM
S. Pastine
1*
, G. Meirson
2**
, R. Banatao
1
, S. Kosinski
1
, M. Nasrullah
1
, V. Ugresic
2
,
F. Henning
3
1
Connora Technologies Inc., 1488 Zephyr Avenue, Hayward, CA USA 94544
*
Phone: +1 (415) 315-9524 Email:**********************
2
Fraunhofer Project Centre, 2544 Advanced Ave, London, Ontario, Canada N6M 0E1
**
Phone: +1 (519) 661-2111 Email:***************
3
Department of Polymer Engineering, Fraunhofer Institute for Chemical Technology ICT, Germany
Abstract
Implementation of composites in automotive manufacturing is driven by cost reduction. High
Pressure Resin Transfer Molding (HP-RTM) allows part manufacturing cycle time to be on the order of
minutes. Thermoset materials used in HP-RTM are not recyclable, which leads to artificially high
production costs due to the lack of a suitable means to reincorporate waste in the value chain. Connora
has developed a series of new epoxy curing agents called Recyclamines®. Use of these curing agents
enables manufacturing of recyclable thermoset products. In the present work, Connora’s higher Tg curing
agents were coupled with Hexion’s commercial epoxy resin to produce epoxy/carbon plaques.
Mechanical properties of the resulting plaques were compared with epoxy/carbon plaques produced using
Hexion’s commercial epoxy resin and curing agent. Mechanical properties of both systems were found to
be similar at room temperature conditions.
Background
Application of composite materials in various technologies in the automotive industry has
recently been on the rise. One such application is HP-RTM, which delivers two or more
components (e.g., resin and curing agent) from separate tanks to the mixing head where they
are mixed and injected into the mold under high pressure to create a thermoset. The mold
usually contains a fiber fabric or a preform made from a fiber fabric. As the liquid thermoset
material is injected into the mold and infused into the fiber fabric, a matrix develops resulting
from the reaction between resin and curing agent. Efficient mixing and fast injection enables the
use of elevated temperature molds, facilitating part production times in mere minutes. Short
cycle times in conjunction with elevated physical performance makes HP-RTM-produced parts
particularly attractive for the automotive industry. One major disadvantage of HP-RTM is
sustainability, however, as neither the thermoset materials nor the carbon fiber reinforcement
are reusable.
Connora Technologies has pioneered the development of recyclable, amine-based curing
agents for epoxy resin to facilitate the creation of recyclable thermoset products and
composites. Connora’s recyclable amine technology has a cleavage point in the center of the
molecule, which under a specific set of conditions, breaks all cross-links in the epoxy matrix.
Thus, cleavage of this bond effectively converts the epoxy thermoset matrix into a thermoplastic
material. Figure 1 displays this reaction scheme. Replacement of recyclable amines for
conventional amine curing agents allows for the recycling and/or repurposing of both matrix and
the fiber fabric in post-manufacturing waste and end-of-life streams.
Page 1
Figure 1: Schematic representation of recyclable epoxy technology
Previous research on the subject of HP-RTM manufacturing [1] focused on reuse of the
fabric by reimpregnation with resin after the original resin matrix had been recycled. The new
composite manufactured from recycled fabric had very similar properties to the initial composite
manufactured from a virgin carbon fabric. In this research, panels (900x550 mm
2
) were
manufactured using Hexion commercial resin in combination with Connora’s newly developed
higher Tg hardener system. Mechanical properties of the resulting panels were tested and
compared with properties of panels manufactured with Hexion’s commercial Resin and
Hardener system.
Materials
Hexion’s Epikote 6000 resin with either Connora’s Recyclamine 3182 or Recyclamine 3382
were loaded into the HP-RTM machine and injected into the mold. SGL supplied the
unidirectional and multidirectional carbon fiber preforms placed in the mold. SGL preforms were
also injected with Hexion’s Epikote 6150 resin and Hexion’s Epikure 6150 hardener. Molding
Page 2
2024年6月13日发(作者：柳俏丽)
HIGHER TG RECYCLABLE HIGH PRESSURE RESIN TRANSFER
MOLDING (HP-RTM) EPOXY PROPERTIES AND HOW THEY
COMPARE TO A COMMERCIAL SYSTEM
S. Pastine
1*
, G. Meirson
2**
, R. Banatao
1
, S. Kosinski
1
, M. Nasrullah
1
, V. Ugresic
2
,
F. Henning
3
1
Connora Technologies Inc., 1488 Zephyr Avenue, Hayward, CA USA 94544
*
Phone: +1 (415) 315-9524 Email:**********************
2
Fraunhofer Project Centre, 2544 Advanced Ave, London, Ontario, Canada N6M 0E1
**
Phone: +1 (519) 661-2111 Email:***************
3
Department of Polymer Engineering, Fraunhofer Institute for Chemical Technology ICT, Germany
Abstract
Implementation of composites in automotive manufacturing is driven by cost reduction. High
Pressure Resin Transfer Molding (HP-RTM) allows part manufacturing cycle time to be on the order of
minutes. Thermoset materials used in HP-RTM are not recyclable, which leads to artificially high
production costs due to the lack of a suitable means to reincorporate waste in the value chain. Connora
has developed a series of new epoxy curing agents called Recyclamines®. Use of these curing agents
enables manufacturing of recyclable thermoset products. In the present work, Connora’s higher Tg curing
agents were coupled with Hexion’s commercial epoxy resin to produce epoxy/carbon plaques.
Mechanical properties of the resulting plaques were compared with epoxy/carbon plaques produced using
Hexion’s commercial epoxy resin and curing agent. Mechanical properties of both systems were found to
be similar at room temperature conditions.
Background
Application of composite materials in various technologies in the automotive industry has
recently been on the rise. One such application is HP-RTM, which delivers two or more
components (e.g., resin and curing agent) from separate tanks to the mixing head where they
are mixed and injected into the mold under high pressure to create a thermoset. The mold
usually contains a fiber fabric or a preform made from a fiber fabric. As the liquid thermoset
material is injected into the mold and infused into the fiber fabric, a matrix develops resulting
from the reaction between resin and curing agent. Efficient mixing and fast injection enables the
use of elevated temperature molds, facilitating part production times in mere minutes. Short
cycle times in conjunction with elevated physical performance makes HP-RTM-produced parts
particularly attractive for the automotive industry. One major disadvantage of HP-RTM is
sustainability, however, as neither the thermoset materials nor the carbon fiber reinforcement
are reusable.
Connora Technologies has pioneered the development of recyclable, amine-based curing
agents for epoxy resin to facilitate the creation of recyclable thermoset products and
composites. Connora’s recyclable amine technology has a cleavage point in the center of the
molecule, which under a specific set of conditions, breaks all cross-links in the epoxy matrix.
Thus, cleavage of this bond effectively converts the epoxy thermoset matrix into a thermoplastic
material. Figure 1 displays this reaction scheme. Replacement of recyclable amines for
conventional amine curing agents allows for the recycling and/or repurposing of both matrix and
the fiber fabric in post-manufacturing waste and end-of-life streams.
Page 1
Figure 1: Schematic representation of recyclable epoxy technology
Previous research on the subject of HP-RTM manufacturing [1] focused on reuse of the
fabric by reimpregnation with resin after the original resin matrix had been recycled. The new
composite manufactured from recycled fabric had very similar properties to the initial composite
manufactured from a virgin carbon fabric. In this research, panels (900x550 mm
2
) were
manufactured using Hexion commercial resin in combination with Connora’s newly developed
higher Tg hardener system. Mechanical properties of the resulting panels were tested and
compared with properties of panels manufactured with Hexion’s commercial Resin and
Hardener system.
Materials
Hexion’s Epikote 6000 resin with either Connora’s Recyclamine 3182 or Recyclamine 3382
were loaded into the HP-RTM machine and injected into the mold. SGL supplied the
unidirectional and multidirectional carbon fiber preforms placed in the mold. SGL preforms were
also injected with Hexion’s Epikote 6150 resin and Hexion’s Epikure 6150 hardener. Molding
Page 2