5% Borated Polyethylene | JCS Nuclear Solutions

JCPE5 is a 5% boron loaded polyethylene neutron shield – HMW grade. Specifically developed for neutron shielding purposes in nuclear installations; its optimal boron content of 5% provides excellent attenuation of thermal neutrons, thus reducing the levels of capture-gamma radiation.

JCPE5 has a high hydrogen content, making it an effective fast neutron shield, slowing down fast neutrons to low energy thermal (slow) neutrons, which are then absorbed by the added boron compound.

JCPE5 5% Borated Polyethylene is typically used in neutron shielding applications where low and intermediate-levels of neutron flux are expected, but elevated temperatures are not. JCPE5 is available in a wide range of form factors including sheets, bricks, cylinders, pellets, and other custom shapes.

It is easily machined using common wood and metalworking tools. John Caunt Scientific can not only provide custom machining but can also pour JCPE5 into custom made moulds to provide application-specific shielding forms.

Features at a glance

available as slabs, bricks, pellets, rods and spheres
Other dimensions/shapes on request
Can be supplied machined to close tolerances
Other boron loadings available on request
Self-extinguishing version available (see model JC207)

Uses

Neutron Shielding
Linac Bunkers
Moderator
Instrument Shielding
Wall Shielding

JCS Borated Polyethylene Neutron Shielding

Specifications

	Standard	Units	Value
Properties
Colour	-	-	White
Density	ISO 1183-1	g/cm³	1.04
Thermal Properties
Melting temperature (DSC, 10°C (50°F) / min)	ISO 11357-1/-3	°C	135
Glass transition temperature (DSC, 20°C (68°F) / min)	ISO 11357-1/-2	°C	-
Thermal conductivity at 23°C (73°F)	-	W/(K.m)	≥ 0.38
Coefficient of linear thermal expansion (-40 to 150 °C) (-40 to 300°F)	ASTM E-831 (TMA)	µin./in./°F
Coefficient of linear thermal expansion (23 to 100°C) (73°F to 210°F)	-	µm/(m.K)	135
Heat Deflection Temperature: method A: 1.8 MPa (264 PSI)	ISO 75-1/-2	°C	45
Continuous allowable service temperature in air (20.000 hrs)	-	°C	80
Min. service temperature	-	°C	-20
Flammability: UL 94 (3 mm (1/8 in.))	-	-	HB
Flammability: Oxygen Index	ISO 4589-1/-2	%	<20
Tensile strength	ISO 527-1/-2	MPa	21
Tensile strain (elongation) at yield	ISO 527-1/-2	%	7
Tensile strain (elongation) at break	ISO 527-1/-2	%	7
Mechanical Properties
Tensile modulus of elasticity	ISO 527-1/-2	MPa	1600
Shear Strength	ASTM D732	MPa
Compressive stress at 1 / 2 / 5 % nominal strain	ISO 604	MPa	14/ 21 / 29
Compressive strength	ASTM D695	PSI	-
Charpy impact strength - unnotched	ISO 179-1/1eU	kJ/m²	15,0
Charpy impact strength - notched	ISO 179-1/1eA	kJ/m²	5C
Charpy impact strength - double 14° notched	ISO 11542-2	kJ/m²	8
Izod Impact notched	ASTM D256	ft.lb./in
Flexural strength	ISO 178	MPa	-
Flexural modulus of elasticity	ISO 178	MPa	-
Relative volume loss during wear test "sand-slurry" : TIVAR® 1000=100	ISO 15527	-	350
Shore hardness D	ISO 868	-	66
Electrical Properties
Electric strength	IEC 60243-1	kV/mm	-
Volume resistivity	IEC 62631-3-1	Ohm.cm	10E13
Surface resistivity	ANSI/ESD STM 11.11	Ohm/sq.	10E12
Dielectric constant at 1 MHz	IEC 62631-2-1	-	-
Dissipation factor at 1 MHz	IEC 62631-2-1	-	-
Miscellaneous
Specific Gravity	ASTM D792	-	-
Water absorption after 24h immersion in water of 23°C (73°F)	ISO 62	%	< 0.1
Water absorption at saturation in water of 23 °C (73°F)	ASTM D570	%	-
Wear rate	ISO 7148-2	µm/km	-
Dynamic Coefficient of Friction (-)	ISO 7148-2	-
Limiting PV at 100 FPM	QTM 55007	ft.lbs/in².min	-
Limiting PV at 0.1 / 1 m/s cylindrical sleeve bearings	-	Mpa.m/s	- / -
NYP: there is no yield point
Note: 1 g/cm³ = 1,000 kg/m³ ; 1 MPa = 1 N/mm² ; 1 kV/mm = 1 MV/m