Premium
Decreasing paint cost for sheet molding compound ( SMC ) compression molding
Author(s) -
Cai Kaiyu,
Bhuyan Mohammad S. K.,
Zhang Dan,
Villarreal Maria G.,
Straus Elliott J.,
Lee L. James,
Castro Jose M.
Publication year - 2021
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.25569
Subject(s) - materials science , primer (cosmetics) , composite material , coating , sheet moulding compound , compression molding , molding (decorative) , carbon black , electrical conductor , mold , porosity , powder coating , adhesive , carbon nanotube , natural rubber , layer (electronics) , chemistry , organic chemistry
Finishing, in most cases, is the most expensive step for manufacturing plastic parts in automotive and truck industry; being electrostatic painting is the desired approach for improved quality. For plastic parts to be painted electrostatically, a conductive primer needs to be applied first. In the case of SMC compression molded parts, in‐mold coating (IMC) is the primer material of choice, as it also serves to fill the surface porosity typical in SMC parts. To make the IMC conductive, the current approach is to add carbon black (CB), which results in a black colored primer. In this research, single wall carbon nanotube (SWCNT) was evaluated, as an alternative to CB, to develop a clearer version of conductive IMC. The effect of SWCNTs on both degree of lightness and electrical conductivity was experimentally evaluated. The results indicate that a clearer and slightly more conductive coating than standard IMC can be obtained by adding 0.15 wt% SWCNTs into the base IMC resin, which results in approximately 12.5% paint saving compared to standard IMC. The processability of the modified coating was shown to be only slightly less favorable than standard coating.