Cross over point! Plantation output of NR exceeds that of wild (ca. 55/75,000 tons plantation to 66/49,000 tons of wild).

Methyl rubber was used to make vehicle tyres and also converted to synthetic ‘hard rubber’ for battery boxes and other ‘ebonite’ applications.

Patented latex concentration by centrifugation.

Patented manufacture of foams from latex as apposed to dry rubber.

General Tyre & Rubber Co formed. Later to become Gencorp Inc.

First organic vulcanization systems without sulphur: nitrobenzene and peroxides(About this time the importance of zinc oxide in accelerated cures was appreciated.).

The first practical patent for chlorinated rubber. Solutions as varnishes and corrosion- resistant paint.

Patented production of thermal blacks from natural gas.

Introduced the first rubber ‘internal mixer’.

Invented the ‘V’ belt.

Invented ‘Vulcalock’ for bonding natural rubber to metal.

Discovered the effect of diphenylguanidine (DPG).

World production of NR 350,000 tonnes.

Prevulcanization of latex and its use to manufacture dipped goods.

Natural rubber production 350,000 tons, only 37,000 tons wild.

Developed aldehyde-amine antidegradents.

Formed Cooper Corp, later Cooper Tyre & Rubber Co.

Discovered the pre-vulcanization of latex.

Mercaptobenzothiazole (MBT) discovered.Independently.

 

Stephenson Reduction Plan introduced to cut output and force up the price of natural rubber. A disaster and soon withdrawn.

Thiurams introduced.

Xanthates introduced.

Suggested making rubber thread by extruding latex through a jet into a coagulating bath.

Columbian Carbon introduced a range of furnace blacks.

Introduced cotton tyre cord.

Patented modern process – extrusion of compounded latex through multiple glass jets into coagulating bath with continuous draw-off of threads for drying/curing.

Zinc dithiocarbamates introduced.

Patented organic fatty acid/zinc oxide use in vulcanization.

Revertex formed in Malaysia to produce latex concentrate by a heat process.

Fossilized rubber 60,000,000 years old found.

MC and HG/HAW independently develop the first commercially feasible antioxidants.

Serious work began on the synthesis of Synthetic polybutadiene (Buna).

The first commercial use of cyclised rubber as metal-rubber bond interface.

First commercial antioxidants (amines) introduced - Staining.

Rubber Research Institute of Malaysia formed under Dr G Bryce. Took over research labs of the Rubber Growers Association.

Quote: "Synthetic rubber is dead".

Working for BF Goodrich, put cyclized rubber on a commercial footing. Materials ranged from gutta percha-like to shellac-like thermoplastic resins. Used in ‘Vulcalock’ process to bond vulcanized rubber to most serfaces for chemical protection.

He began to build ‘Fordlandia’ – a complete town in the jungle with (eventually) a plantation of over a million rubber trees.

Patented "Thiokol" - first commercial synthetic rubber. Note that this is not a S cure! just metal oxides and possibly quinones.

Suggested diffusion after vulcanization of protective agents into rubbers to extend life.

World production of NR 850,000 tons.

Buna N and Buna NN discovered (nitrile rubbers of 25% ACN and 35% ACN).

Introduction of amine derivative antioxidants (still staining).

DuPont Invented Duprene. Became polychloroprene (Neoprene).

Forms Bridgestone Co Ltd.

Discovered sulphenamides - adducts of MBT with amines.

Observed that rubber extract can be added to rubber to improve its ageing.

Russia manufactured SKA - followed by SKB (polybutadiene rubbers).

Synthetic rubbers first featured in statistics at 2,000 tons.

Invented the ‘simple’ ‘O’ ring seal.

Buna S patented and produced (Styrene butadiene copolymer).

Tropical leaf blight wiped out the plantation of ‘Fordlandia’. Fordlandia 2 begun but again wiped out. The end of Brazil’s dream of a rubber plantation industry.

Sovprene. equivalent to neoprene.

Introduced ‘Pliofilm’ (rubber hydrochloride) as a thin transparent packaging film although patented a couple of years or so earlier.

IG and Metallgesellschaft both used chlorinated rubber to bond steel and nitrile rubber or polychloroprene.

Institut Francais du Caoutchouc set up in Paris.

Rubber Stichting (foundation) established.

Developed urethane rubbers.

Butyl rubber.

British Rubber Producers Research Association created. Later Malaysian Rubber … (MRPRA) then Tun Abdul Razak Research Centre ( TARRC).

Introduced rayon tyre cord.

Claimed the word “latex” was in use as early as 1662.

First use of plasticized PVC as cable sheath.

Nitrile rubber produced in the States.

SKI - polymerised isoprene (synthetic "NR").

NR production 1,500,,000 tons, synthetics 150,000 tons.

Took out the first patent for injection moulding rubber articles.

GR-S production started (now known as SBR). Government rubber-styrene -> styrene butadiene rubber (c.f. Buna S).

First patent relating to urethane rubbers.

Nitrile rubber lattices used for many dipped goods. Use of PVME to heat coagulate and thus make thick films with a single dip also found (by accident).

Triisocyanate triphenyl methane developed as a rubber-metal bonding agent. Known today as Desmodur R.

Silicone rubber. Not a sulphur cure, peroxides used.

Introduced nylon tyre cord.

Michelin introduced the radial tyre (the cords run bead-to-bead at 90° to the wheel direction).

DuPont develops fluoropolymers.

Acetate rubbers developed.

NR production 1,900,000 tons, Synthetics 800,000 tons.

Introduction of Phenolic antioxidants (some non staining).

Last wild rubber exported.

Pirelli launches its steel belted radial the ‘Cinturato’.

Announced high cis synthetic "NR" based on Ziegler/Natta catalysts.

Introduction of substituted para-phenylenediamine antiozonants (still staining).

Low cis synthetic "NR".

Michelin imports first radials into USA.

Introduced fluoroelastomers.

NR production overtaken by the synthetics.

NR production 2,000,000 tons, Synthetics 2,500,000 tons.

Introduced polyester tyre cord.

Albany Court built in London above St James Underground station. The first building to rest solely on natural rubber anti-vibration mounts.

Urethane crosslinking of NR discovered.

NR production 3,000,000 tons, Synthetics 5,750,000 tons.

Dunlop introduced the ‘tubeless’ tyre.

Thermoplastic rubbers which have the properties of a vulcanizate at ‘room temperature’ but can be moulded and re-moulded at high temperatures start to become important.

Introduced thermoplastic natural rubber.

World NR production 3,850,000 tons, Synthetics 8,250,000 tons.

The Law and Justice centre in San Bernadino County was the first building to be supported on high damping (earthquake resisting) natural rubber bearings.

Epoxidised natural rubber became commercially available – chemically modified to move into areas unique to the synthetics (oil-resistant and high damping).

NR production 5,200,000 tons, Synthetics 9,300,000 tons.

Perhaps 5 billion plantation "hevea braziliensis" trees producing rubber worldwide.

World NR production 6,500,000 tons, Synthetics 8,700,000 tons.