Phenolic Resins
and
Phenolic Molding Compounds
Greg Spaeth
Project Engineer,
Materials Engineering Laboratory
Plastics Engineering Company
Presented at 2013 SPE Thermoset Division TOPCON
Phenolic Resins
Phenolic resins are synthesized in a pressure
vessel by repeatedly linking phenolic monomers
with aldehyde chemicals
Typically phenol and
formaldehyde
Other phenols include
Cresol
Cashew nutshell oil
Another aldehyde used
Furfural
Process variations can result in a
assortment of resin structures each
demonstrating a wide range of
properties
There are Two Types of Phenolic Resins
Novolac
Molar excess of phenol
Require an external curing agent
Two Stage
Usually hexamethylenetetramine or “Hexa”
Two year shelf life
Resol
Typically there is a molar excess of formaldehyde
Do not require an external curing agent
Single Stage
Six month shelf life
Phenolic Molding Compounds
Phenolic Molding Compounds
Phenolic Molding Compounds are produced by compounding
various fillers with Phenolic Resin
Typical Formula
50 % Phenolic Resin, resol or novolac
45 % filler
Woodflour
Minerals, talc, clay, ATH, etc.
Cotton
Glass Fibers
Carbon Fibers or graphite powder
5 % colorants and lubricants
Carbon Black
Zinc Stearate
The Oil and Natural Gas
Mining Process
as a Case Study for
Phenolic Materials
A well begins by drilling a large diameter hole extending below the fresh water
A surface casing is inserted to isolate fresh water and support the blow out preventer
Cement is pumped into the casing
The cement is forced out of the casing and up the well hole sealing of the aquifer
Wiper Plugs and
Darts
Phenolic
Core
Over molded rubber shell
Why Phenolic Molding Compounds?
The molded phenolic core provides superior strength and rigidity to
enable the wiper plug to withstand the high pressures involved in
forcing hundreds of cubic feet of concrete through the well casing
High Modulus provides stiffness and stability for the darts mandrel
core and tighter griping for the elastomer wiper segments
Heat resistance allowing plugs rated for use at 400ºF
Easy drill out with small debris
The wiper plug is then drill out and the production well is drilled.
Production casing is lowered
It takes more than 350 casings weighing more then 85 tons to case a 10,500 foot well
Cement is once again pumped into the well
Again using a wiper plug the cement is force back up the well securing the casing
Fracturing the well then begins by lowering a perforation gun down the well casing
Small shaped explosives blast holes through the casing, cement, and into the formation
Fracturing fluid is pumped into the well
The fluid under extreme pressure causes the formation to fracture
Resin Coated Proppant Sand
Fracturing fluids varies among regions and well types, but typically consists of
water (90+%) proppant (9%) and chemicals (<2%)
Resin Coated Proppant Sand
Once the fracturing fluid is removed, the phenolic resin coated sand remains behind and
works as a prop to keep the fissures from sealing on release of pressure
Why Phenolic Resin?
Phenolic’s high modulus and excellent heat and creep resistance resists
fracture under pressure as proven in industry “Conductivity test”
Why Phenolic Resin?
Chemical Resistance
harsh chemicals found down hole can attack various proppant
including ceramic proppant
Curable Proppant
Enables the proppant to remain in place in wells with high pressure flow
The now fractured portion of the well is sealed off using fracturing ball
Fracturing Balls
Fracturing Balls
Why Phenolic Molding Compound?
Phenolic Balls offer an excellent combination of
chemical and heat resistance with superior tensile
and compressive strength compared with other
plastic balls.
Customizable formulations allowing a specific gravity
range of 0.8 to 3.5+
The perf gun is again lowered and detonated
The perf gun is again lowered and detonated
Again fracturing fluid is pumped into the well to fracture the new
section of the well while the already fractured section is isolated by the
frac ball
Fracturing Balls
Perforation and well fracturing is repeated as often as needed
Once fracturing is complete the balls are usually drilled or floated out
Surface equipment is put in place
Well begins production
Valve Components
Valve Components
Why Phenolic Molding Compounds?
Strength, rigidity, dimensional stability, creep resistance
A phenolic back-up ring allows internal pressure to anchor the seat
within the valve body and prevents seat walking
Non-collapsible, stretch resistant, blow out proof, field replaceable
Non-collapsible, stretch resistant, blow out proof, field replaceable
Chemical resistance and high hardness
Provide valve components that resists corrosive environments and do
not deform under pressure allowing for repeated ball sealing
Other Applications
Corrosive coatings for
Storage tanks, semi tank trailers, railroad tank cars, fans blowers, and fin tube coils
Binder for
Friction pads, brake pads, grinding wheels, plywood and particle board
Wear Resistance
Gas meter valves, pump seals, caster wheels
Dimensional Stability &Thermal Performance
Brake pistons, transmission parts, electrical motor brush cards
Electrical insulation
terminal strips, commutators, capacitor cans and caps
Offshore Applications
Why Phenolic Resin?
Superior Creep Resistance
Strength and stability under load
Low weight high strength and modulus
Strength and rigidity
Chemically Resistant
Harsh marine environment
Excellent flammability resistance and low smoke and toxicity
Increased level of safety
High carbon and char yield
Retains level of strength and integrity should fire break out
Phenolic Properties
Chemical Resistance
Transmission oil,150ºC (302ºF)
Salt water, 65ºC (150ºF)
Beach, 65ºC (150ºF)
Unleaded gasoline, 22ºC (72ºF)
E85 Unleaded gasoline, 22ºC (72ºF)
SAE 30 Motor oil, 150ºC (302ºF)
Propylene glycol, 100ºC (212ºF)
Crude oil, 22ºC (72ºF)
Phenolic Properties
Chemical Resistance
Phenolic Properties
Chemical Resistance
Phenolic Properties
Chemical Resistance
Phenolic Properties
Chemical Resistance
Phenolic Properties
Chemical Resistance
Phenolic Properties
Comparison of Phenolic molding compound to engineering grade thermoplastics
Thermoplastics
20% fiber glass filled ABS
20% fiber glass filled Acetal
20% fiber glass filled PPA
20% fiber glass filled PPS
20% fiber glass filled Nylon66
Phenolic Molding Compound
Glass and mineral filled
PLENCO 06404 glass and mineral filled
PLENCO 02311 general purpose woodflour filled
Data for PLENCO materials available from PLENCO.com, all thermoplastic data from matweb.com overview average values
Phenolic Properties
Hardness
Data for phenolic and PLENCO
materials are approximated from E scale
Data for PLENCO materials available from PLENCO.com, all thermoplastic data from matweb.com overview average values
Phenolic Properties
Strength and modulus
Data for PLENCO materials available from PLENCO.com, all thermoplastic data from matweb.com overview average values
Phenolic Properties
Strength and modulus
Data for PLENCO materials available from PLENCO.com, all thermoplastic data from matweb.com overview average values
Phenolic Properties
Compressive Strength
Data for PLENCO materials available from PLENCO.com, all thermoplastic data from matweb.com overview average values
Phenolic Properties
Heat Resistance
Phenolic Properties
Flammability resistance
UL V-0 at 0.5mm
IEC 60695 Glow Wire GWFI and GWFI Rating 960ºC+ at 0.75mm
ASTM E162 Flame Spread 0.85*
*Source: Composites World
Author: Michael LeGault
Posted on: 2/14/2013
Phenolic Properties
Post bake
What is it?
•
Postbaking is a manufacturing step where molded parts are heated in an
oven after being removed from the die.
Why do it?
•
•
•
•
Dimensional stabilize a part, especially for high temperature applications
Out-gas residual ammonia which is a by product of two stage cure
Improve strength
Sometimes only because the print tells you to
How is it done?
•
•
Ramp oven from room temperature to 15ºC below parts initial tg at 5º/min
Ramp oven to desired temperature at 0.5-0.25ºC/min to keep the oven
temperature under the parts instantaneous tg
Do I need to do it?
•
Many Applications do not require a postbake, only a thorough
understanding of the reasons to postbake will help you answer this question
Thank You
Questions?
Greg Spaeth
Project Engineer,
Materials Engineering Laboratory
Plastics Engineering Company
Presented at 2013 SPE Thermoset Division TOPCON