Study of dynamically cured PP/MAH‐g‐PP/talc/epoxy composites

Abstract

In the present study, an epoxy resin was dynamically cured in a polypropylene (PP)/maleic anhydride-grafted PP (MAH-g-PP)/talc matrix to prepare dynamically cured PP/MAH-g-PP/talc/epoxy composites. An increase in the torque at equilibrium showed that epoxy resin in the PP/MAH-g-PP/talc composites had been cured by 2-ethylene-4-methane-imidazole. Scanning electron microscopy analysis showed that MAH-g-PP and an epoxy resin had effectively increased the interaction adhesion between PP and the talc in the PP/talc composites. Dynamic curing of the epoxy resin further increased the interaction adhesion. The dynamically cured PP/MAH-g-PP/talc/epoxy composites had higher crystallization peaks than did the PP/talc composites. Thermogravimetric analysis showed that the addition of MAH-g-PP and the epoxy resin into the PP/talc composites caused an obvious improvement in the thermal stability. The dynamically cured PP/MAH-g-PP/ talc/epoxy composites had the best thermal stability of all the PP/talc composites. The PP/MAH-g-PP/talc/epoxy composites had better mechanical properties than did the PP/MAH-g-PP/talc composites, and the dynamically cured PP/MAH-g-PP/talc/epoxy composites had the best mechanical properties of all the PP/talc composites, which can be attributed to the better interaction adhesion between the PP and the talc. The suitable content of epoxy resin in the composites was about 5 wt %.

Mechanical, barrier, and thermal properties of poly(lactic acid)/poly(trimethylene carbonate)/talc composite films

“…The results showed that a suitable content of talc in the composites was about 2 wt %. When used in appropriate amounts, it led to obvious improvements in the mechanical properties of the composites, but additional increases in the amount of talc did not improve the mechanical properties any more …”

High‐temperature platinum‐catalyzed hydrosilylation and dehydrocoupling cross‐linking of silicones

“…The transparency of the obtained silicone materials (cross‐linked PMHS and cross‐linked V‐PDMS/PMHS) indicates the absence of aggregation of platinum particles. A carbon–carbon triple bond on the periphery of the complex differs PCC from the known modified Karstedt's catalysts 23,28,29 . We believe that this functional group is capable of incorporating the polymer chain by the hydrosilylation with the hydride‐containing polysiloxane, which prevents the aggregation of the complex particles during the reaction.…”

“…Also, J. Li et al 28 synthesized thermostable platinum(II) phosphineacetylide complexes for α , ω ‐vinyl‐terminated polydimethylsiloxane and polymethylhydrosiloxane (PMHS) cross‐linking at 120°C. Authors 29 proposed a series of phosphite ligands by transesterification, which were used in combination with Karstedt's catalyst to cross‐link vinyl‐ and hydrid‐containing silicones at 150°C. However, in general, there is a lack of information about thermally stable catalysts, which can catalyze both hydrosilylation and dehydrocoupling cross‐linking of functional polysiloxanes with vinyl (–CH=CH 2 ) and/or hydride (Si–H) groups above 100°C.…”

“…6 Moreover, during the silicone rubber fabrication and/or when various fillers are introduced into them to improve mechanical strength or impart special properties, it becomes necessary to carry out polysiloxane cross-linking at temperatures above 100 C. [23][24][25][26][27] In this regard, study of thermally stable platinum catalysts for producing silicone materials seems to be a challenge. I. Kownacki et al 23 used Karstedt's catalyst derivatives with tris(triorganosilyl)phosphite ligands for the hydrosilylation cross-linking of polysiloxanes at 120 C. Also, J. Li et al 28 synthesized thermostable platinum(II) phosphineacetylide complexes for α,ω-vinyl-terminated polydimethylsiloxane and polymethylhydrosiloxane (PMHS) cross-linking at 120 C. Authors 29 proposed a series of phosphite ligands by transesterification, which were used in combination with Karstedt's catalyst to cross-link vinyland hydrid-containing silicones at 150 C. However, in general, there is a lack of information about thermally stable catalysts, which can catalyze both hydrosilylation and dehydrocoupling cross-linking of functional polysiloxanes with vinyl (-CH=CH 2 ) and/or hydride (Si-H) groups above 100 C.…”

Effects of dynamical cure and compatibilization on the morphology and properties of the PP/epoxy blends

“…Glass fiber and inorganic fillers are often used to enhance the modulus and stiffness of PP [13,14]. Our laboratory has applied dynamical vulcanization to prepare a new type of PP/epoxy blends with the structure of crosslinked epoxy resin particles dispersed in the PP matrix [15][16][17]. The blends were prepared in the mixing chamber of a Haake rheometer RC90 through dynamical curing an epoxy resin by 2-ethylene-4-methane-imidazole (EMI-2,4 ) in the molten PP.…”