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Today "polymer" is a word in every chemistry textbook. A hundred years ago, the idea behind it was a minority view that many respected chemists thought was wrong. Hermann Staudinger spent about a decade arguing that giant molecules exist. This post explains what he claimed, why others objected, how he settled it, and a calculation that shows the scale he was talking about.
Do you need polymers for JEE or NEET?
Check your own syllabus first. The current NCERT Class 12 Chemistry Part II has no polymers unit, and the JEE (Main) 2026 syllabus mentions polymerisation only as a reaction of alkenes and alkynes. The JEE (Advanced) 2026 brochure does list a Polymers topic, including types of polymerisation, natural rubber, cellulose and nylon. Proteins, starch and cellulose, which Staudinger also called macromolecules, still appear in biomolecules for every exam. Syllabi change, so read your own year's document.
What did chemists believe before Staudinger?
Rubber, cellulose and starch were awkward substances. They did not have sharp melting points, they formed sticky, viscous solutions and they would not crystallise neatly. Their solutions behaved like colloids, and the leading view treated them as colloids.
In his Nobel Lecture of 11 December 1953, Staudinger described the situation. Solutions of these substances looked much like soap solutions, and soaps were known to form micelles: loose clusters of small molecules held together by weak forces. So it seemed natural to assume that rubber or cellulose particles were micelles too. Several researchers believed the clusters were built from small molecules.
What did Staudinger claim?
Staudinger began working on these substances in 1920 at the Federal Institute of Technology in Zurich, and that year published a paper titled "Über Polymerisation" (On polymerisation) in the *Berichte der deutschen chemischen Gesellschaft*. In 1922, with Jakob Fritschi, he published work on the hydrogenation of rubber and its constitution.
His claim was that the particles are not clusters at all, but single molecules: long chains in which every link is an ordinary covalent bond. The presentation speech for his 1953 prize summarises it: in the early 1920s he held that a molecule could be very large, of 10,000 or 100,000 atoms, and that the particles of many colloidal solutions were molecules of this type. The speech adds that the argument was "very strange in the early 1920's" and that "the next ten years were charged with controversy"; the theory was not universally recognised until the 1930s.
How did he prove it?
The idea is elegant. If a rubber or cellulose particle is a loose cluster, then changing the chemistry of its small molecules should change how they pack, and the cluster should fall apart or change size. If the particle is one long covalent chain, you can convert it into a derivative and the chain length should stay the same.
In his Nobel Lecture, Staudinger called these *polymer-analogous* transformations. He showed that a polymer can be turned into a derivative "without any change in the degree of polymerization", which proves that the units in the colloid particles "are linked together by chief valences" (covalent bonds), "in other words the colloid particles are macromolecules". He also used solution viscosity: for long, thread-like molecules, the viscosity of solutions of equal concentration rises with chain length.
How big is a macromolecule? A worked example
In his lecture, Staudinger drew a rough boundary: substances with a molecular weight above about 10,000, that is, molecules of a thousand or more atoms, behave as macromolecules.
Problem. Polystyrene is made from styrene, C₈H₈. How many repeat units and atoms are in a polystyrene chain of molar mass 10,000 g/mol? Take C = 12.011 and H = 1.008 g/mol, and ignore end groups.
Molar mass of one repeat unit: 8 × 12.011 + 8 × 1.008 = 96.088 + 8.064 = 104.152 g/mol.
Degree of polymerisation: n = 10,000 ÷ 104.152 ≈ 96 repeat units.
Atoms: each unit has 8 + 8 = 16 atoms, so about 96 × 16 ≈ 1,536 atoms.
So even a chain at Staudinger's lower boundary holds about 1,500 atoms. A sample of molar mass 104,152 g/mol has exactly 1,000 repeat units and about 16,000 atoms. Ordinary organic molecules in your syllabus have tens of atoms.
Common mistakes:
Using the molar mass of the polymer chain in place of the monomer when finding n. Always divide polymer mass by repeat-unit mass.
Forgetting that addition polymers like polystyrene keep every atom of the monomer, while condensation polymers lose a small molecule such as water at each link.
Treating n as exact. Synthetic polymers are mixtures of chains of different lengths, as Staudinger stressed, so molar masses are averages.
What came after?
The presentation speech notes that by the 1930s industry had adopted the macromolecular theory for making plastics. In the US, Wallace Carothers used it to design nylon. Staudinger received the 1953 Nobel Prize in Chemistry "for his discoveries in the field of macromolecular chemistry". The Nobel biography records that he wrote about 500 papers on macromolecules from 1920, and that his wife, Magda Woit, was for many years his co-worker and co-author.
What can a student learn from Staudinger?
Design a test that splits two ideas. He did not just argue; he found a chemical change that a cluster and a chain would survive differently.
Keep the rules you trust. He insisted the same bonding rules apply to large and small molecules. When a new topic looks strange, check whether old rules still explain it before inventing new ones.
Expect time. It took about a decade for his view to win. If a method feels slow to pay off in your own study, that is normal.
For the exam-side chemistry, read our post on addition and condensation polymers. If you cannot picture how a chain forms from monomers, the Fermi Concept Library has every concept in chemistry with its own lesson, so you can fill that one gap and return to your notes.
Try this now: find n and the number of atoms for a polyethene chain (repeat unit C₂H₄) of molar mass 28,000 g/mol.
