The insulation on the pipe cleaner is fine (I tested it) and the only difficulty is getting good electrical contact at the ends.
It is best to burn off the end insulation and then scrape the metal with a knife / emery paper until the metal is seen to be shiny.
Your null result is due to a number of factor the main one being that the magnetic field produced by your electromagnet is very small and only realistically detected with a compass or a sensitive magnetometer.
You can make one by straightening a paper-clip and then stroking along the paper-clip with a magnet to magnetise the paper-clip.
I used a large paper-clip as then as a compass it is more sensitive to changes in the magnet field around it.
You can then either float the paper-clip on water but putting in on an upturned bottle top weighted down with some Blu-Tack or suspending it from a fine thread which is what I did.
The tread was about $70\,\rm cm$ long anchored on a table top with some Blu-Tack.
You will find that if the paper-clip is suspended from its centre it aligns with the Earth's magnetic field even to the extent that it inclines along the line of the non-horizontal Earth's magnetic field lines.
For ease of use adjust the point of suspension so that the paper-clip was horizontal.
Take a steel screw and tested it by bringing it close to the compass and often you will find it is magnetised because one end of the screw repels one end of compass.
Both ends of an unmagnetised steel screw would attract a compass.
If you wished you could demagnetise the steel screw by heating it to red heat whilst it is orientated in a magnetic East-West direction.
Wind a few turns of pipe cleaner around the screw connected it to a $1.5 \,\rm V$ C-type battery (or one that is close at hand) using finger and thumb and you might notice that the ends got warm.
Bring the electromagnet close to the compass, note the effect on the compass and then reverse the battery and again note the effect on the compass.
Hopefully that you will get attraction with the battery connected one way and repulsion with the battery connected the other way around.
In some ways all this is "old school" and you can use an iPhone to detect magnetic field.
The magnetometer is at the top right of the iPhone and I used the app Sensor Kinetic Pro which I downloaded from the Apple app store.
Here is a screen shot of the recorded magnetic field before and after I switched on the electromagnet which shows how small the field due the electromagnet is.
As a final point think of what you had at hand, a battery, a pipe cleaner etc and what you did not have, eg a compass, a reel of insulated copper wire, etc and then remember that Faraday and other also lacked basic "off the self" apparatus.
They had to make the apparatus as they went along and to me it makes their discoveries all the more remarkable.