Page 144 - Handbook of Plastics Technologies
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THERMOSETS


                             3.14                        CHAPTER 3


                                      TABLE 3.9  Phenolic Moldings: Typical Properties
                                               Property         Wood flour  Glass fiber

                                        Specific gravity           1.33       1.85
                                        Tensile strength, kpsi    7         13
                                        Flexural strength, kpsi  11         38
                                        Compressive strength, kpsi  28      48
                                        Impact strength, fpi      0.4        9

                                        Elongation, %             0.6        0.2
                                                      o
                                        Heat deflection temp.,  C  168       246
                                                      –6 o
                                        Thermal expansion, 10 / C  38       15
                                        Linear mold shrinkage, %  0.7        0.3
                                        Dissipation factor        0.17       0.055
                                        Water absorption, %       0.9        0.6


                                         TABLE 3.10  Fillers for High-Impact-Strength Phenolics

                                             Filler     Notched Izod impact strength, fpi

                                          None                    0.25
                                          Wood flour               0.3
                                          Fabric                  2.4
                                          Cord                    7.0


                                     TABLE 3.11  Effect of Fiber Length on Phenolic Impact Strength

                                             Fiber          Notched Izod impact strength, fpi
                                      Ramie fiber, 1 in                1.0

                                      Ramie fiber, 4 in                2.4
                                      Sisal fiber, 1/8 to 1/4 in       3.9
                                      Sisal fiber, 1–2 in              10.0
                                      Tire cord, 1/2 in               10.1
                                      Tire cord, 1 in                 17.0






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