01561nas a2200169   4500008004100000020002000041022002000061245008100081210006900162260001400231300001100245520097100256100002101227700001401248700001701262856011201279       2017                        eng d  a978-149876758-3  a978-149876757-600aInsertion or ziegler-natta polymerization of olefins: science and technology0 aInsertion or zieglernatta polymerization of olefins science and   bCRC Press  a31-1163 a<p>One of the most disruptive discoveries of twentieth century has been metal-catalyzed polymerization of ethylene to polyethylene by Prof. Karl Ziegler from the Max Plank Institut Fuer Kohlenforschung, Mulheim, Germany. This discovery marked the beginning of an era, which revolutionized the field of chemistry, in particular, the field of polymer chemistry in many aspects and saw an avalanche of patents and publications. Unlike typical academic discoveries, this invention did not stop at the academic labs, but led to the development of a large-scale process that produces about 180 million tons of polyolefins (annually) today. 1 But the very obvious question that comes to our mind is what prompted Prof. Ziegler to react ethylene with the two components (that we will discuss later in this chapter)? It was not an overnight realization, but instead, it was rational analysis of a serendipitous observation and systematic experimentation by Prof. Ziegler.</p>1 aChikkali, S., H.1 aPatel, K.1 aNetalkar, S.  uhttps://library.ncl.res.in/content/insertion-or-ziegler-natta-polymerization-olefins-science-and-technology02092nas a2200229   4500008004100000022001400041245009700055210006900152260000900221300001200230490000700242520133000249653002101579653002301600653001501623653001401638653002501652100002001677700001901697700002101716856012501737       2025                        eng d  a1060-132500aWaste polyethylene to long-chain unsaturated esters and alcohols via alkene cross-metathesis0 aWaste polyethylene to longchain unsaturated esters and alcohols   cAUG   a660-6680 v623 a<p>
	The conversion of waste polyethylene into valuable long-chain functional molecules offers a contemporary solution to the global plastic waste challenge. This study presents a two-step catalytic approach, comprising of polyethylene (PE) dehydrogenation followed by cross-metathesis with renewable resource-derived functional olefins, catalyzed by the Grubbs-II catalyst (G-II). A dehydrogenated polyethylene (DHP) was subjected to a tandem catalytic cross-alkene metathesis with functional olefins under mild conditions to achieve approximately 36% conversion of DHP into valuable long-chain building blocks with controlled product distribution. Comprehensive characterization of intermediates and products was performed using NMR, GC, GC-MS, GPC, and DSC. In the alkene cross-metathesis with methyl-10-undecenoate, the product distribution consisted of 23% lower alkenes (C8-C14), 40% unsaturated long-chain mono-esters (C12-C18), and 37% unsaturated di-esters. In the case of 10-undecen-1-ol, the distribution included 20% lower alkenes (C8-C11), 32% unsaturated long-chain (C12-C18) mono-alcohols, and 48% unsaturated di-alcohols. This strategy opens up new opportunities for converting waste polyethylene into high-value chemical intermediates, enabling resource recovery and delivering environmental benefits.</p>
10adepolymerization10afunctional olefins10aMetathesis10aRecycling10aValue-added products1 aKhopade, K., V.1 aBodkhe, D., V.1 aChikkali, S., H.  uhttps://library.ncl.res.in/content/waste-polyethylene-long-chain-unsaturated-esters-and-alcohols-alkene-cross-metathesis