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3. Use of Regrinds

Content Introduction Molding Conditions Use of Regrind Mold Design
  Mold Shrinkage and Dimensional Accuracy Safety Precautions Molding Defects Countermeasures

Use of regrind is possible; however, molding material of 100% regrind will have mechanical and thermal properties slightly degraded by the breakage of glass fibers and, moreover, change in hue may occur. When using a recycled material, it is recommended to use a material which is blended regrind in a constant ratio below 25%. Table 3-1 shows property retention of 1140A1 when mixed with a recycled material, and Table 3-2 shows property retention of 1140A1 when the whole amount is used for three times repeatedly.

Under UL standards, use of up to 25% regrinds is approved. Further, in some grades, use of up to 50% regrind is possible. For details, please refer to Yellow Card (File no. E109088).

 

 

Table 3-1 Property Retention of DURAFIDE® 1140A1 When Mixed
                 with Regrind
Item
Property retention (%)

Content of regrind (%)
0
30
50
70
100
Tensile strength
100
99
98
97
96
Elongation
100
103
102
102
104
Flexural strength
100
99
97
98
97
Flexural modulus
100
102
100
99
100
Izod impact strength Notched
100
103
97
99
90
Unnotched
100
99
100
95
97
Change in hue (ΔE) *
-
2.2
3.0
3.5
5.0
 

*

  Change in hue is shown by the value of Δ instead of retention rate.

 

 

Table 3-2 Property Retention of DURAFIDE® 1140A1 after Recycling
                 Whole Amount Three Times
Item
Property Retention (%)
Granulated
Reclaimed pellet
Tensile strength
82
78
Tensile elongation
100
97
Tensile modulus
90
-
Flexural strength
87
85
Flexural modulus
94
89
Izod impact strength Notched
72
51
Unnotched
84
75
Heat distortion temperature under load *
97
97
Change in hue (ΔE) **
13.8
-
Melt index
-
220
Shrinkage (Flow dir.)
-
135
  * 1.82MPa
  **
  Change in hue is shown by the value of ΔE instead of retention rate.

 

 

Content Introduction Molding Conditions Use of Regrind Mold Design
  Mold Shrinkage and Dimensional Accuracy Safety Precautions Molding Defects Countermeasures