تطبيقات البلمرة الضوئية على نفايات البوليمرات المعاد تدويرها

Abstract

رُذسج هزِ انذساسخ فٍ إطبس رثًٍُ انُفبَبد ورحضُش يىاد حُىَخ يجزكشح راد قًُخ يضبفخ فٍ يدبل ردشَجُب إنً رحضُش ورقُُى خصبئص كًجىصَذ سٍُ (Composite رشيُى األسُب.ٌ َهذف هزا انعًم (Dentalيحضش ثزقُُخ انجهًشح انضىئُخ نغشض ثهذف يحبكبح نىٌ وشكم وثُُخ انسٍ انطجُعُخ. َزكىٌ انًشكت يٍ شق عضىٌ َضى انًىَىيُشاد GMA-Bis و TEGDMAوثبدئ ضىئٍ .DMAEMA/Camphorquinoneهزا انشق انعضىٌ يذعى ثشق غُش عضىٌ وهى انهُذسوكسٍ اثبرُذ HAp يبدح حُىَخ يسزخشخخ يٍ َفبَبد عظبو انجقش انًطعًخ ثأكسُذ انسُشَىو 2CeOوأكسُذ انالَثبَىو 3O2La رًذ يزبثعخ كفبءح عًهُخ انجهًشح انضىئُخ وحسبة دسخخ انجهًشح (%DC (ثبسزخذاو رذسَدُب فٍ دسخخ انجهًشح اَخفبضب رقُُخ يطُبفُخ األشعخ رحذ انحًشاء .(ATR/FTIR (أظهشد انُزبئح يع صَبدح َسجخ انحشى يقبسَخ ثبنعُُخ انًشخعُخ غُش انًحشىح انزٍ ثهغذ َسجخ ثهًشرهب .94% 60 ويع رنك، حققذ انحشىاد انًطعًخ ثـ 2CeO نربئح ثهًشح أفضم ثكثُش يقبسَخ ثـ 3O2La. يٍ خهخ أخشي، أظهشد َزبئح قُبسبد االيزصبصُخ (Wsp (وانزوثبَُخ (Wsl (فٍ وسظ يبئٍ َحبكٍ يىاصَب نهكًجىصَذ انسٍُ انًذعى ثبنحشىاد 2CeO -HAp فٍ يقبويخ انزحهم انًبئ.ٍ كًب رفىقب ثُئخ انفى أَضب وخىد اسرجبط عكسٍ ثٍُ دسخخ انجهًشح وكم يٍ االيزصبصُخ وانزوثبَُخ؛ حُث كهًب اسرفعذ نىحع (%DC)اَخفضذ كم يٍ Wsp و Wsl َزُدخ رشكم شجكخ ثىنًُشَخ أكثش كثبفخ رقهم يٍ انفشاغبد انذاخهُخ ورحذ يٍ َفبر خضَئبد انًبء داخم انًبدح.This study falls within the framework of waste recovery and the preparation of innovative bioactive materials with added value in the field of dental restoration. This work aims experimentally to prepare and evaluate the properties of a dental composite prepared by the photopolymerization technique to approximate, as closely as possible, the color, shape, and structure of the natural

tooth. The compound consists of an organic phase containing the monomers Bis- GMA and TEGDMA and a photoinitiator Camphorquinone/DMAEMA. This

organic phase is reinforced with an inorganic phase, which is hydroxyapatite (HAp), a bioactive material extracted from bovine bone waste doped with cerium oxide (CeO2) and lanthanum oxide (La2O3). The efficiency of the photopolymerization process was monitored and the degree of conversion (DC%) was calculated using FTIR/ATR spectroscopy. The results showed a gradual decrease in the degree of conversion with the increase in filler content compared to the unfilled reference sample, which reached a polymerization rate of 60.94%. Nevertheless, fillers doped with CeO2 achieved significantly better polymerization results compared to La2O3. On the other hand, the results of water sorption (Wsp) and solubility (Wsl) measurements in an aqueous medium simulating the oral environment showed a parallel superiority of the dental composite reinforced with HAp-CeO2 fillers in resistance to hydrolytic degradation. An inverse correlation was also observed between the degree of conversion and both sorption and solubility; as DC% increased, both Wsp and Wsl decreased due to the formation of a denser polymer network that reduces internal voids and limits the penetration of water molecules into the material.