Effect of peroxide concentration on the modification of the LLDPE : Statistical experimental design and thermal properties

• Published in: Polymer bulletin (Berlin, Germany) Vol. 54; no. 1-2; pp. 117 - 122
• Main Authors: RAMOS, Valéria D, DA COSTA, Helson M, PEREIRA, Anderson O, ROCHA, Marisa C. G, GOMES, Ailton De S
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.05.2005; Berlin Springer Nature B.V; New York, NY
• Subjects: Applied sciences; Chemical modifications; Chemical reactions and properties; Crystallization; Design of experiments; Dicumyl peroxide; Exact sciences and technology; Factorial design; Heat of fusion; Low density polyethylenes; Melt flow index; Melt temperature; Melting; Organic polymers; Physicochemistry of polymers; Temperature effects; Thermodynamic properties; Chain elongation; Crystallinity; Experimental study; Melt index; Property processing relationship; Free radical reaction; Thermal properties; Structure processing relationship; Chemical modification; Experimental design; Olefin polymer; Factorial design; Linear low density ethylene polymer; Organic peroxide; Rheological properties
• ISSN: 0170-0839; 1436-2449
• DOI: 10.1007/s00289-005-0360-y

SummaryThe effect of small concentrations of dicumyl peroxide (DCP) on the modification of a linear low density polyethylene (LLDPE) during a reactive extrusion process was investigated. The experiments were arranged in a two level factorial design in order to evaluate the effect of temperature zones (X1), peroxide concentration (X2) and screw rpm (X3) on the modification of LLDPE. The melt flow index (MFI) was used as a response variable. It was verified that the thermal properties, crystalline melting temperature (Tm), the heat of fusion (ΔHmelt) and the crystallinity degree (X%) decrease with the increasing of the peroxide concentration. The crystallization temperature (Tc) increased up to 0.05% w/w peroxide, whereafter the level stays almost constant. The gel content of the samples however indicated that a three-dimensional network was negligible in the experimental conditions used.