Plastic Pipes Conference Association # 2023 Lake Buena Vista
Carlos Domínguez, Predrag Micic, Rafael Juan, Nuria Robledo, Rafael A. García-Muñoz
Slow Crack Growth (SCG) resistance is the main property that must be controlled for assessing the long-term performance on polyethylene resins used for pipe application. The latest generation of bimodal and multimodal ethylene-α-olefin copolymers with exceptional balance of mechanical properties and processability have been developed in the last years. The inclusion of branched chains, preferentially in the high molecular weight region, has been crucial to favor the entanglements and tie molecules formation. In the present work, different PE100 and PE100RC resins have been evaluated following the different standards for measuring the SCG performance. All the resins have similar molecular weight and short chain branching distribution, but different comonomer type: C4, C5 and C6, which permitted the evaluation of the influence of the short chain branching length on SCG phenomena.
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