I am trying to achieve a similar effect to the one in Live and Let Die....
 
https://youtu.be/e7aGAIWe3uE?t=58s 
 
It sounds like the kind of thing that would be categorised under FX in a string library but I cannot find anything.
 
Does anyone know of any libraries (Kontakt or others) that would be able to recreate this sound?
 
Thanks
ZT

Pitch bend, maybe?
Could be an example of one of those things you just can't really do with MIDI

Yes,I thought maybe pitch bend.

Or maybe use a portamento/glide function if the sampler/synth has one.

Thanks, I have tried various things and pitchbend seems to be the only option that gets close. 
 
I am assuming that the original had a number of violinists doing a very slow downward glissando so I think I will need a number of separate violin tracks each slowly lowering their pitch at different rates (to mimic the differences created by individual humans playing each instrument). 

ZincTrumpet
I am assuming that the original had a number of violinists 

Yes, very much so. A single violin just doesn't sound like what you picture when you think "strings". When programming string parts, you will always get a more realistic sound if you program individual parts. Orchestrate your firsts and seconds, your violas, cellos and basses as seperate lines, as if you had an orchestra.
 
Or, why not find some violin players locally and get them in to record? Much more fun and rewarding than looking at a computer screen.
 

In an ideal world but that would take too long to organise and I don't have much time.
 
I did try various Glissando/Portamento options in a number of virtual orchestral instruments but I couldn't make them glide slowly enough.
 
Thanks again for your inputs.

When layering lots of strings it’s a good idea to very slightly de-tune them against each other, and introduce a little bit of pitch variation in what each individual instrument is playing as well.

The violin family, having no frets, tend to wander a tiny amount in pitch both between players and how exactly each player fingers and bows each note. That, along with a bit of vibrato, again at slightly varying speeds, is what gives a string section its “fatness”. Though traditional folk fiddlers and baroque music specialists tend to use less vibrato than the modern orchestral players.

Learn violin.
 
 
 
 
 
(kidding of course. Although for this purpose alone, violin or maybe viola is slated on m bucket list)

To answer my own question I picked up a freebie over Christmas - 8DIO Cage Unleashed Free Try Pack.
 
This has, amongst other things, the sound I am looking for - select Textures I and play a G :)