Cardboard Packaging in Geant4 Material List

Greetings,

I was looking for a material similar to ‘cardboard’ utilised for packaging in Geant4 libraries, but I could not find either the exact ‘cardboard’ or some similar material like paper. Can you please assist me to find – or even define – a material similar to a cardboard?

The Geant4 NIST materials list contains four different cellulose derivative, which is probably the closest you’ll get to “cardboard” (i.e., dried wood pulp):

 3    G4_CELLULOSE_CELLOPHANE       1.42      77.6   
 3      G4_CELLULOSE_BUTYRATE        1.2      74.6   
 4       G4_CELLULOSE_NITRATE       1.49        87   
 3         G4_ETHYL_CELLULOSE       1.13      69.3   

You’ll probably need to do a bit of searching online to find out what’s most appropriate. You’ll also want to set the density yourself to match the density of whatever you’re using in real life.

According to this article, ‘Preparation and Properties of Cellulose-Based Films Regenerated from Waste Corrugated Cardboards Using [Amim]Cl/CaCl_2’ For a P-WCC (i.e., Pre-treated Waste Corrugated Cardboard), this material definition shall suffice for representing cardboard; although density is not defined, but an amount of 0.72-0.8 g/cm^3 seems reasonable.

void DefineP_WCC_Material() {
    G4NistManager* nist = G4NistManager::Instance();

    // Define elements
    G4Element* C  = nist->FindOrBuildElement("C");
    G4Element* H  = nist->FindOrBuildElement("H");
    G4Element* O  = nist->FindOrBuildElement("O");
    G4Element* Ca = nist->FindOrBuildElement("Ca");

    // === Component Materials ===

    // Cellulose: C6H10O5
    G4Material* Cellulose = new G4Material("Cellulose", 1.5*g/cm3, 3);
    Cellulose->AddElement(C, 6);
    Cellulose->AddElement(H, 10);
    Cellulose->AddElement(O, 5);

    // Hemicellulose (Xylan): C5H8O4
    G4Material* Hemicellulose = new G4Material("Hemicellulose", 1.4*g/cm3, 3);
    Hemicellulose->AddElement(C, 5);
    Hemicellulose->AddElement(H, 8);
    Hemicellulose->AddElement(O, 4);

    // Lignin: C10H12O3
    G4Material* Lignin = new G4Material("Lignin", 1.3*g/cm3, 3);
    Lignin->AddElement(C, 10);
    Lignin->AddElement(H, 12);
    Lignin->AddElement(O, 3);

    // Calcium Carbonate: CaCO3
    G4Material* CalciumCarbonate = new G4Material("CalciumCarbonate", 2.7*g/cm3, 3);
    CalciumCarbonate->AddElement(Ca, 1);
    CalciumCarbonate->AddElement(C, 1);
    CalciumCarbonate->AddElement(O, 3);

    // Water: H2O
    G4Material* Water = new G4Material("Water", 1.0*g/cm3, 2);
    Water->AddElement(H, 2);
    Water->AddElement(O, 1);

    // === Final Composite Material ===

    G4Material* P_WCC = new G4Material("P_WCC", 0.8*g/cm3, 5);  // Estimated density

    P_WCC->AddMaterial(Cellulose,        82.32 * perCent);
    P_WCC->AddMaterial(Hemicellulose,     7.11 * perCent);
    P_WCC->AddMaterial(Lignin,            7.65 * perCent);
    P_WCC->AddMaterial(CalciumCarbonate,  1.92 * perCent);
    P_WCC->AddMaterial(Water,             2.00 * perCent);
}