As PLA is not soluble in water, you can hear about "hydrophobic" interactions in several discussions. It is more informative to have a look at Hansen solubility parameters. For details see: Hansen, Charles (2007). Hansen Solubility Parameters: A user's handbook, Second Edition. Boca Raton, Fla: CRC Press. Values you can find in: Rafael Auras, Loong-Tak Lim, Susan E. M. Selke, Hideto Tsuji, Poly(Lactic Acid): Synthesis, Structures, Properties, Processing, and Applications, Wiley, 2010, pp.84-87.  Hansen solubility parameters show contributions for disperse interaction, but also remarkable contributions from polar and hydrogen bonding terms in your case (PLA and dichloromethane).

This could give a very sound inkling as to the tussle between the two compounds:

http://www.thingiverse.com/thing:73120

Thank you so much :)