Immidiately after the rapture the world will usher in tribulation. This kind of scene the world has never has never experienced potrayed in Rev chapters 8&9. But then could there be repentance and salvation during this time?.
Yes there will be those saved thro the preaching of the 144,000 and the 2 witnesses but they will have to sacrifice their lives. Isn't it better to serve Christ now? The Anti-christ will demand worship and when they refuse they will be killed.
Rev 7:9 & 13-14 "After this I looked and a vast host appeared which no-one could count (gathered out) of every nation,from all tribes and peoples and languages. ...Who are these (people)clothed in long white robes? And from where did they come? ...and he said to me, They are those who have come out of the great tribulation (persecution), and have washed their robes and made them white in the blood of the Lamb.
"Rev 15:2 "Then I saw what seemed to be a glassy sea blended with fire, and those who had come off victorious from the beast and from its statue and from the number corresponding to his name were standing beside the sea, with harps of God in their hands..."