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The high volume of plastic waste and the extremely low recycling rate have created a serious challenge worldwide. Local distributed recycling and additive manufacturing (DRAM) offers a solution by economically incentivizing local recycling. One DRAM technology capable of processing large quantities of plastic waste is fused granular fabrication, where solid shredded plastic waste can be reused directly as 3D printing feedstock. This study presents an experimental assessment of multi‐material recycling printability using two of the most common thermoplastics in the beverage industry, polyethylene terephthalate (PET) and high‐density polyethylene (HDPE), and the feasibility of mixing PET and HDPE to be used as a feedstock material for large‐scale 3‐D printing. After the material collection, shredding, and cleaning, the characterization and optimization of parameters for 3D printing were performed. Results showed the feasibility of printing a large object from rPET/rHDPE flakes, reducing production costs by up to 88%. Highlights: Study: multi‐material recycling printability of PET‐HDPE.Large‐scale fused particle‐based 3‐D printing technically possible.Direct waste 3‐D printing rPET/rHDPE flakes, reducing production costs up to 88%. [ABSTRACT FROM AUTHOR]

ABSTRACT Polymers containing o-nitrobenzyl esters are promising for preparation of light sensitive materials. o-Nitrobenzyl methacrylate has already been polymerized by controlled ATRP or RAFT. Unfortunately, the radical polymerization of o-nitrobenzyl acrylate (NBA) was not controlled until now due to inhibition and retardation effects coming from the nitro-aromatic groups. Recent developments in the Single Electron Transfer-Living Radical Polymerization (SET-LRP) provide us an access to control this NBA polymerization and living character of this NBA SET-LRP is demonstrated. Effects of CuBr2 and ligand concentrations, as well as Cu(0) wire length on SET-LRP kinetics are shown presently. A first-order kinetics with respect to the NBA concentration is observed after one induction period. SET-LRP proceeds with a linear evolution of molecular weight and a narrow distribution. High initiation efficiency close to 1 and high chain-end functionality (∼93%) are reached. Chain extension of poly( o-nitrobenzyl acrylate) is realized with methyl acrylate (MA) to obtain well defined poly( o-nitrobenzyl acrylate)-b-poly(methyl acrylate) (PNBA- b-PMA). Finally, light-sensitive properties of PNBA are checked upon UV irradiation. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 2192-2201 [ABSTRACT FROM AUTHOR]

ABSTRACT Poly( d,l-lactide- co-glycolide) (PLGA) copolyesters are commonly used in biomedical applications. Researches were carried out on nontoxic or low-toxic catalysts that are enough efficient to provide short polymerization times, adequate microstructure chains and similar properties than the commercial PLGA materials. In this study, PLGA were synthesized by ring-opening copolymerization (ROP) using three different catalysts. Stannous octoate is the first catalyst we used, as it is very efficient, even its toxicity is still on debate. Two others low-toxic catalysts [zinc lactate and bismuth subsalicylate (BiSS)] were also evaluated. The comparison of these ROP was realized in terms of kinetics and control of the polymerization. Then, the influence of the catalyst on the PLGA microstructure chains is reported. Finally, abiotic hydrolytic degradation rate is studied. Results described in this article show that BiSS is one very attractive catalyst to produce low toxic PLGA for biomedical applications. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1130-1138 [ABSTRACT FROM AUTHOR]

ABSTRACT A cholesterol-based liquid crystal monomer, diethylene glycol cholesteryl ether acrylate (DEGCholA), has been successfully polymerized by atom transfer radical polymerization (ATRP) for the first time. Appropriate experimental conditions to control the polymerization of DEGCholA have been investigated using a model initiator (ethyl 2-bromoisobutyrate) in tetrahydrofuran (THF) or toluene at 60 °C. Well-controlled ATRP of DEGCholA was obtained using N, N, N′, N′, N″-pentamethyldiethylenetriamine as ligand in THF at 60 °C. These conditions were then applied to initiate the ATRP of DEGCholA from multifunctional macroinitiators based on dextran. Using a protection/deprotection synthetic scheme, novel graft glycopolymers (Dex- g-PDEGCholA) have been synthesized. The mesomorphic properties of DEGCholA, PDEGCholA, and Dex- g-PDEGCholA have been studied by thermal polarizing optical microscopy, differential scanning calorimetry, and X-ray scattering. PDEGCholA and Dex- g-PDEGCholA show an interdigitated smectic A phase (SmAd) between Tg (∼30 °C) and around 170 °C. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3829-3839 [ABSTRACT FROM AUTHOR]

The synthesis of amphiphilic dextran- g-poly(methyl methacrylate) glycopolymers (Dex- g-PMMA) is studied using 'grafting from' concept and atom transfer radical polymerization. Two strategies have been examined to control the macromolecular parameters of such glycopolymers. One is involving four steps including a protection/deprotection approach and the second one only two steps. The introduction of initiators group onto a protected acetylated dextran (and directly onto dextran) was achieved resulting in protected DexAcBr (and in unprotected DexBr). These two types of polysaccharidic macroinitiators differ in term of solubility (hydrophilic DexBr vs. hydrophobic DexAcBr) and of position of the initiators groups on the glucosidic units (which are the sites of the future grafts). When evaluated as macroinitiators for ATRP of MMA, control was achieved in both cases but DexBr gave much faster polymerization and lower average grafting efficiency compared with DexAcBr or model initiator. Advantages and drawbacks of both pathways have finally been discussed. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 [ABSTRACT FROM AUTHOR]