I did a quick research and found this site for the effects of chemicals on rubbers.
https://mykin.com/rubber-chemical-resistance-chart-3It doesn’t specify the concentration of the chemicals, time of contact, test methodology etc. so still leaves a grey area for ethanol in petrol at varying concentrations.
I am looking for sources to see more detailed research results.
One point to bear in mind is the political impetus behind ethanol for ICE use. It involves considerations of combustion/emissions plus agriculture policies. “Let’s grow our own bio-mass to make ethanol instead of oil use”. Pay farmers to convert.
Oil companies....”Hmmmm....how can we slow down the change to suit us?”
Intoday’s world of online information it is easy to sow seeds of bullshit that are adopted as truth. Finding definitive unbiased information is not always easy.
