The Effect of Dialkyl Peroxide Crosslinking on the Properties of LLDPE and UHMWPE

Abstract

Peroxide has been considered a chemical agent that can be used to tune the properties of polymeric materials. This research evaluated the influence of different concentrations of dialkyl peroxides on the mechanical, thermal, and morphological properties of linear low-density polyethylene (LLDPE) and ultra-high molecular weight polyethylene (UHMWPE). The neat polymer, as well as those with the addition of 1% and 2% by mass of dialkyl peroxides, were subjected to compression molding and immersion in water for 1 h, under controlled temperatures of 90 °C. The values of the gel content found in the samples indicated that the addition of peroxide to the LLDPE and to the UHMWPE promoted the formation of a reticulated network. The structure obtained by the crosslinking led to less reorganization of the chains during the crystallization process, resulting in the formation of imperfect crystals and, consequently, in the reduction in melting temperatures, crystallization and enthalpy. The mechanical properties were altered with the presence of the crosslinker. The polymers presented had predominant characteristics of a ductile material, with the occurrence of crazing with an increased peroxide content.

Crosslinked polyethylene: A review on the crosslinking techniques, manufacturing methods, applications, and recycling

“…The physical behavior (thermal stability, density, crystallization, and tensile properties) of crosslinked PE was also reported to change depending on the initial polymer molecular structure. [ 86 ] Liu et al [ 87 ] studied the effect of DCP content (0.3, 0.5, 1.0, 1.5, 2.0, and 2.5 wt%) on the properties of LDPE. It was found that increasing the DCP content led to higher crystallization temperature, degree of crystallization and elongation at break, while decreasing the tensile strength.…”

Regulating the structure of crosslinked polyethylene and its application in ultra‐high voltage cables

“…Building desirable crystalline and amorphous hierarchal structures has an effect on the processing technology application of PE. Different approaches have been used to control the superstructures and hierarchical structures, govern the crystalline and amorphous regions of the PE matrix, which can confer high performance to the product 5–8 . Therefore, designing in situ experiments to observe the changes in PE crystals and amorphous structures is crucial for structural control and material application.…”

Effect of magnesium hydroxide and graphene nanoplatelets on the properties of peroxide cross‐linked linear low‐density polyethylene nanocomposite

“…[1][2][3] Furthermore, it increases the maximum operating temperature of PE because of the strong cross-linked network formation, making neat PE an ideal material for many applications, in particular cable and wire coating. 4,5 Currently, peroxide cross-linking is one of the widely used methods for PE cross-linking because of its ease of processing and lower cost investment, 6,7 and the use of organic peroxide as an initiator to generate free radicals during the cross-linking process. 8,9 An important limitation of PE is the poor flammability property that limits the scope of its application as a suitable material for fire protection.…”