What is FRPP
FRPP (glass fiber reinforced polypropylene) is a modified polypropylene material produced with glass fibers treated with coupling agents. It is corrosion-resistant, high-temperature resistant, high-pressure resistant, hygienic and non-toxic, recyclable, and suitable for transporting corrosive liquids (alkali liquids) and municipal water supply and drainage systems. I
t has excellent impact resistance and tensile strength, is lightweight, and is easy to install and maintain. Due to its unique properties, FRPP is widely used in the chemical, chemical fiber, chlor-alkali, dye, water supply and drainage, food, medicine, sewage treatment, electrolysis and other industries.
FRPP Chemical and physical properties
Under rated temperature and pressure conditions, FRPP pipes can be safely used for over 50 years. They resist corrosion from most chemicals and can withstand a wide pH range of 1-14, dealing with high concentrations of acids and bases. The maximum operating temperature is 95 degrees Celsius. With a thermal conductivity only 1/200th of steel pipes, these products offer superior insulation performance.
FRP vs FRPP
FRPP (glass fiber reinforced polypropylene) is a subclass of FRP (fiber reinforced plastic). FRP encompasses composite materials made of a polymer matrix reinforced with fibers such as glass, carbon, and aramid; FRPP specifically refers to polypropylene reinforced with glass fibers.
Fibre-reinforced plastic (FRP) (also fibre-reinforced polymer) is a composite material made of a polymer matrix reinforced with fibres. The fibres are usually glass, carbon, aramid, or basalt. Rarely, other fibres such as paper or wood or asbestos have been used. The polymer is usually an epoxy, vinylester or polyester thermosetting plastic; phenol formaldehyde resins are still in use.
FRPs are commonly used in the aerospace, automotive, marine, and construction industries. They are commonly found in ballistic armor as well.
FRP Advantages and limitations
FRP allows the alignment of the glass fibres of thermoplastics to suit specific design programs. Specifying the orientation of reinforcing fibres can increase the strength and resistance to deformation of the polymer. Glass reinforced polymers are strongest and most resistive to deforming forces when the polymers fibres are parallel to the force being exerted, and are weakest when the fibres are perpendicular.
Thus this ability is at once both an advantage or a limitation depending on the context of use. Weak spots of perpendicular fibres can be used for natural hinges and connections, but can also lead to material failure when production processes fail to properly orient the fibres parallel to expected forces.
When forces are exerted perpendicular to the orientation of fibres the strength and elasticity of the polymer is less than the matrix alone. In cast resin components made of glass reinforced polymers such as UP and EP, the orientation of fibres can be oriented in two-dimensional and three-dimensional weaves. This means that when forces are possibly perpendicular to one orientation, they are parallel to another orientation; this eliminates the potential for weak spots in the polymer.
Material requirements
A thermoset polymer matrix material, or engineering grade thermoplastic polymer matrix material, must meet certain requirements in order to first be suitable for FRPs and ensure a successful reinforcement of itself.
The matrix must be able to properly saturate, and preferably bond chemically with the fibre reinforcement for maximum adhesion within a suitable curing period.
The matrix must also completely envelop the fibres to protect them from cuts and notches that would reduce their strength, and to transfer forces to the fibres. The fibres must also be kept separate from each other so that if failure occurs it is localized as much as possible, and if failure occurs the matrix must also debond from the fibre for similar reasons.
Finally the matrix should be of a plastic that remains chemically and physically stable during and after the reinforcement and moulding processes.
To be suitable as reinforcement material, fibre additives must increase the tensile strength and modulus of elasticity of the matrix and meet the following conditions; fibres must exceed critical fibre content; the strength and rigidity of fibres itself must exceed the strength and rigidity of the matrix alone; and there must be optimum bonding between fibres and matrix.