Some of the manufacturers use HDPE of high stiffness and good impact strength for this application. Only after the introduction of samsonite luggage in India and the availability of PP. VIP has started moulding the luggage shells with PP.
This market is now mostly dominated by PP Impact Copolymer. The raw material properties required of this grade are as follows:
Medium to high imapct strength Low blush (less stress whitening) Good stiffness
Sometimes HDPe or LLDPE is added to PPCP to get low blush.
Repol B030MG or B120 MA is used. Samsonite uses DSM grade Stamylan 75MR10.
Generally preferred grade of HDPE is Ladene M 80064.
Polypropylene moulded with Polypropylene
grade used in this application
separators and their covers with metal inserts the batteries are placed near the heat source, is modified with a heat stabiliser additive.
The preferred Impact Copolymer grade is Samsung BJ 500. C080MT.
The equivalent Repol grade is
Generally, automotive parts are moulded with PP Impact Copolymers or compounded PP Homo or Imapct Copymers. The Impact Copolymers require a good impact/stifness balance. TO enhance impact strength, EPDM is added to PPCP and melt compounded. These are used in aprts like bumpers. Parts with long flow paths and varying thicknesses require high flow grades. Controlled Rheology can be used to mould these parts without warpage.
The following grades are used; depending on the properties desired:
C015EG B030MG B120 MA B22MN