Ptsd from borderline personality disorder? I was told that the emotions from borderline personality disorder are so strong that it can cause so much trauma it gives you ptsd is this true?

Chicken/ egg?? This sounds a bit hard to track but... Individuals with borderline personality disorder have been traumatized in some manner early in life. Their behaviors and beliefs may make them vulnerable to particular stressors throughout their life. Examples are that depression and ptsd are seen more often in individuals with borderline personality disorder than the general population.
Complex PTSD. People who are repeatedly traumatized during important developmental periods -- and those traumatized for extensive periods even later in life -- may develop a complex form of ptsd whose characteristics clinically resemble borderline pd. http://www.ptsd.va.gov/professional/pages/complex-ptsd.asp parental abuse and neglect are far more widespread than we'd like to admit. Results are painful.
Yes. Also experiences in which borderline pd individuals get into can be highly traumatizing. In reverse, trauma in childhood is associated with the genesis of future bpd in many cases. Genetic tendencies, and environmental factors might help cause bpd, by some authors.
Many . Many patients become borderline from being under tremendous amounts of stress or pressure. They develop coping mechanisms that actually can cause more harm because of the pressure that they are under. This can lead them to be in more and more difficult situations. Ptsd is usually linked to a significant trauma or stress in the past, so it is certainly possible that patients with borderline may have co-existing ptsd.