Section III Foaming Container
I. Overview
1, the definition of foam plastic gas dispersed in the solid polymer to form a non-foaming hole lightweight polymer materials, also known as microporous plastic or porous plastic.
2, the performance characteristics of foam 1 a small density, light weight, high specific strength and specific stiffness, can reduce transport costs;
2 has excellent impact absorption.
3 Water Absorption Property 4 When the temperature changes, it has good stability 5PH value is neutral, good resistance to various chemical products 6 low thermal conductivity.
3, classification 1 by the cell structure:
Open-cell foam closed-cell foam 2 according to the degree of hardness:
Soft foam foam: Flexible, low compression hardness, restitution after stress relief Rigid foam: Hardness in compression Most rigid foam: Between the first two 3 Density (Foam magnification)
Low density foam (high foam): Density <0.1g/cm3, Foaming ratio> 9
Medium Density Foam (Neutral Foam): Density of 0.1<0.4g/cm3, Foaming Ratio 1.5~9
High density foam (low foam): density > 0.4g/cm3, foam ratio <1.5
Second, foaming method
1, physical foaming method:
The method of foaming using physical principles 1 is to press an inert gas under pressure into a molten polymer or a paste-like composite with an inert gas, and then to lower the pressure and increase the temperature so that the dissolved gas is released to expand and foam.
2 The use of low-boiling point liquid vaporizing gas (also called expandable bead method)
The low-boiling point liquid is pressed into the polymer or the liquid is melted into the polymer particles under a certain pressure and temperature, and then the polymer is heated and softened, and the liquid also vaporizes to vaporize and foam.
3 In the plastic after adding the hollow emblem of the ball after curing to form a foam (also known as the combination foam)
2, chemical foaming method Foaming gas is produced by mixing some of the components in the raw material, in the molding process.
1 Foaming gas is generated by the thermal decomposition of the added pyrolyzed foaming agent.
2 Foaming components interact to produce gas.
3. Mechanical foaming uses strong mechanical agitation to entrain air into the resin emulsion, into a uniform foam in a suspension or solution, and then to gel it through physical or chemical changes to cure into a foam. To avoid undercuts
2. Uniform wall thickness, avoiding abrupt changes, resulting in poor fusion, P177 Figure 10-17, Wall thickness difference T/t<3
Minimum wall thickness, (at least three foamed particles are juxtaposed)
Large bead foam ≥ 12mm
Beads foam ≥ 9.5mm
Beads foam ≥ 6.5mm
Mini Beads Foam Plastic ≥ 1.5mm
Edge thickness is not too thin
3, rounded corners
R=3～12mm
Outer corner R ≥ 5mm (Fast corner fusion, low density, easily damaged)
Small particles R ≥ 1.5mm
4, easy to release mold draft angle ≥ 2 degrees, to avoid side scratches
5, the traces on the product 1 filling mouth trace size 8 ~ 24mm
2 traces of parting line 3 traces of steam hole D = 1 to 8 mm
4 Traces of stripping bars
6, foam magnification:
Vapor and solid volume ratio coloring and other self-study
I. Overview
1, the definition of foam plastic gas dispersed in the solid polymer to form a non-foaming hole lightweight polymer materials, also known as microporous plastic or porous plastic.
2, the performance characteristics of foam 1 a small density, light weight, high specific strength and specific stiffness, can reduce transport costs;
2 has excellent impact absorption.
3 Water Absorption Property 4 When the temperature changes, it has good stability 5PH value is neutral, good resistance to various chemical products 6 low thermal conductivity.
3, classification 1 by the cell structure:
Open-cell foam closed-cell foam 2 according to the degree of hardness:
Soft foam foam: Flexible, low compression hardness, restitution after stress relief Rigid foam: Hardness in compression Most rigid foam: Between the first two 3 Density (Foam magnification)
Low density foam (high foam): Density <0.1g/cm3, Foaming ratio> 9
Medium Density Foam (Neutral Foam): Density of 0.1<0.4g/cm3, Foaming Ratio 1.5~9
High density foam (low foam): density > 0.4g/cm3, foam ratio <1.5
Second, foaming method
1, physical foaming method:
The method of foaming using physical principles 1 is to press an inert gas under pressure into a molten polymer or a paste-like composite with an inert gas, and then to lower the pressure and increase the temperature so that the dissolved gas is released to expand and foam.
2 The use of low-boiling point liquid vaporizing gas (also called expandable bead method)
The low-boiling point liquid is pressed into the polymer or the liquid is melted into the polymer particles under a certain pressure and temperature, and then the polymer is heated and softened, and the liquid also vaporizes to vaporize and foam.
3 In the plastic after adding the hollow emblem of the ball after curing to form a foam (also known as the combination foam)
2, chemical foaming method Foaming gas is produced by mixing some of the components in the raw material, in the molding process.
1 Foaming gas is generated by the thermal decomposition of the added pyrolyzed foaming agent.
2 Foaming components interact to produce gas.
3. Mechanical foaming uses strong mechanical agitation to entrain air into the resin emulsion, into a uniform foam in a suspension or solution, and then to gel it through physical or chemical changes to cure into a foam. To avoid undercuts
2. Uniform wall thickness, avoiding abrupt changes, resulting in poor fusion, P177 Figure 10-17, Wall thickness difference T/t<3
Minimum wall thickness, (at least three foamed particles are juxtaposed)
Large bead foam ≥ 12mm
Beads foam ≥ 9.5mm
Beads foam ≥ 6.5mm
Mini Beads Foam Plastic ≥ 1.5mm
Edge thickness is not too thin
3, rounded corners
R=3～12mm
Outer corner R ≥ 5mm (Fast corner fusion, low density, easily damaged)
Small particles R ≥ 1.5mm
4, easy to release mold draft angle ≥ 2 degrees, to avoid side scratches
5, the traces on the product 1 filling mouth trace size 8 ~ 24mm
2 traces of parting line 3 traces of steam hole D = 1 to 8 mm
4 Traces of stripping bars
6, foam magnification:
Vapor and solid volume ratio coloring and other self-study
Pure Water Wipes,Natural Cleaning Wipes,Pure Water Wet Wipes,Pure Water Wipes For Babies
Shandong Tianzige International Trade Co., Ltd , https://www.sdbabydiapers.com