Wallace Hume Carothers holds a place of pride amongst thepantheons of twentieth-century chemists who transformed ourway of thinking, and brought an entirely new perspective toa branch of science. Polymer science flourished in the yearsafter Carothers as never before, and led to the creation of anew industry – vibrant, useful, and exciting. The greatness ofCarothers lies in the profound, yet simple questions he asked,and the clarity and definitiveness with which he provided theanswers. In a short working span of eleven years, he leftbehind an incredible legacy of achievements which ordinarymortals cannot even dream of accomplishing in several lifetimes.This article chronicles the life and times of WallaceCarothers, the men and the institutions that inspired him,his seminal contributions to polymer chemistry; the mood ofmelancholy that permeated his persona and which ultimatelycost him his life.

If Wallace Carothers was the designer, Flory was the architectand builder of the edifice of polymer science. If Carotherswas the composer, Flory was the man who wrote the notes forthe music. Carothers and Flory represent the quintessentialqualities that are needed to make great science – intuition andrationality, experiment and theory, flights of imagination anddiligent reduction to practice, exuberance and rigour.

Fifty-four years after the Nobel Prize was awarded to KarlZiegler and Giulio Natta for the polymerization of olefins bycomplex organometallic catalysts, the field continues to elicitenormous interest, both from the academia and the industry.Furthermore, this chemistry and technology occupy ahigh ground in the annals of 20th-century science. The eleganceand simplicity of Ziegler’s chemistry continue to astoundresearchers even today, and the enormous impact thischemistry has had on the quality of our life is truly incredible.Polyethylene, produced using Ziegler’s chemistry hastouched every aspect of common man’s life, so much so that,today it is impossible to imagine life on this planet withoutpolyethylene. Equally fascinating is the story of how Zieglerstumbled on this most impactful discovery. Ziegler’s disciplineand rigor in systematically following every lead in thelaboratory, however trivial it seemed, and his penchant forunderstanding the basics of science culminated in 1954, witha simple reaction for converting ethylene to polyethylene, thequintessential carbon-carbon (C-C) bond forming reaction.His life and work hold many lessons for all scientists whodream of making their scientific quests useful and relevantto society. It is also relevant to the contemporary debate onbasic versus applied research.

The name of Natta is entwined inextricably with that of Ziegler,in the famous catalyst systems known by their names andused to make polyethylene and polypropylene. Unlike ethylene,which is achiral, propylene is a prochiral molecule andupon polymerization can lead to interesting stereochemicaland regiochemical enchainment sequences. Natta’s presciencein recognizing this unique feature of propylene led to the discoveryof crystalline isotactic polypropylene and the beginningof a new industry. The story of how Natta discoveredpolypropylene is an engrossing one – one of stiff competitionamongst contemporaries, Natta’s intimate relationship withthe Italian industries, and his unique scientific background.Natta’s identification of isotactic polypropylene as a righthandedthree fold ‘single helix’ in March 1954, in quick successionto the discovery of DNA ‘double helix’ by Watson,Crick, and Rosalind Franklin (March 1953), and the coiledcoilmotif of ‘triple helix’ of collagen by G N Ramachandran(August 1954), makes this period the ‘golden age of macromolecularcrystallography’.

The International Year of the Periodic Table, proclaimed bythe United Nations to begin January 2019, coincides with theone hundred and fiftieth anniversary of Mendeleev’s publishedPeriodic Table. The Periodic Table marked the comingof age of Chemistry. Mendeleev’s genius lay not in the discoveryof the fact of periodicity, but in his interpretation of itas a fundamental principle, allowing for concrete hypothesesto be tested. His predictions of the properties of elements-tobe,as well as presentation in a simple and easy to understandchart were contributing factors to make it his lasting legacy.The success of the Periodic Table was a triumph of the valueof understanding chemistry based on theory over merely dependingon empirical observations and an ability to relatesuch theory to experiments. Mendeleev’s discovery emergedout of the difficulties he encountered in teaching chemistryand, interestingly enough, it continues to serve that purposetoday. The Periodic Table is taught worldwide early on inscience education. Regardless of scientific technicalities, thePeriodic Table will always stand as a symbol of the beauty inthe simplicity of nature, an order that permeates a seeminglychaotic world of elements with deep scientific and philosophicalunderpinnings. In this article, we trace the origins of thisepoch-making discovery, his life as well as the times in whichMendeleev lived and worked and the present and future impactof his discovery.