Preparation and Characterization of PE-g-AIt Marco A. da Silva, Griselda B. Galland* Summary: The grafting of HDPE and LLDPE with itaconic acid (AIt) was made by reactive extrusion using the peroxide 2,5-dimethyl-2,5-di(tert-butyli) peroxy hexane (trigonox 101) as initiator. The graft efﬁciency was evaluated using FTIR to identify bands of carbonyl groups in the polymer. It is inﬂuence on the addition of itaconic acid in the structure of the polymer chain was evaluated using CRYSTAF and microcalorimetry, where it was show that the incorporated acid causes a narrow crystallization proﬁle and the decrease of the percentage of the soluble fraction at 30  C. The polymers were fractionated by molecular weight and chemical composition to check the distribution of the AIt incorporation, the percentage of AIt was quantiﬁed in each fraction by FTIR, and it was show that the incorporation of AIt occurred homogeneously in all the chains. Keywords: FTIR; HDPE; LLDPE Introduction The functionalization of poly(propylene) (PP) and polyethylene (PE) through the grafting of unsaturated monomers such as maleic anhydride (MAH), acrylic acid and their derivatives, in the presence of organic peroxide as initiator, [1-5] have received much attention over the past decades. Among the polar groups tested one that has stood out in recent years has been the itaconic acid. In fact, this acid is not only interesting because it can be obtained from renewable sources such as sugar cane (derived from the fermentation generated by aspergilusitaconicus), but also, because it has a dual functionality, which ultimately will provide interesting possibilities as potential monomer for modifying polyole- ﬁns, generating new compounds with dif- ferential properties. [6,7,8,9,10] The reaction of a polar monomer as itaconic acid with a polyoleﬁn in melt ﬂow in the presence of peroxide, might result in the graft of AIt in the chain. In this process some secondary reactions, such as cross- linking and degradation, can also occur, these reactions have a direct effect on the structure and consequently on the crystal- linity of the resin. [11,12] Up to now, only a few studies [13] have been reported on the effect of such comonomers insertion in the polymeric chain on crystallization. In the present work, it is show a methodology to study Linear Low Density Polyethylene (LLDPE) and High Density Polyethylene (HDPE) grafted with Itaconic acid (AIt). This work also aims to evaluate the crystallinity in samples of LLDPE using CRYSTAF for HDPE samples, it was used microcalorimetry instead of CRYSTAF due to the presence of crosslinked material coming from the grafting process. HDPE samples were also fractionated by molecu- lar weight while LLDPE samples were fractionated by chemical composition with reference for temperature sample collec- tion the fraction the proﬁle CRYSTAF. The amount of acid itaconic was determinated by FTIR. Experimental Part Grafted Samples were Obtained Using the Following Conditions The incorporation of polar monomer (AIt) into the polymer chain was made by reactive extrusion in a twin screw extruder ZSK-16. The polymers studied were LLDPE (MFI ¼ 29g/10 0 , density: 0.924 g/cm 3 ) and Instituto de Química da UFRGS Porto Alegre - Brazil E-mail: griselda.barrera@ufrgs.br Macromol. Symp. 2013, 330, 177–184 DOI: 10.1002/masy.201300025 | 177 Copyright ß 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim wileyonlinelibrary.com