Pressure fibrillar structure

Crystallizable polymers tend to form randomly oriented crystallites which are oriented when the polymer is stretched or cold drawn at temperatures below the Tm. Crystallization under pressure may result in a fibrillar structure or extended chain structure. 

Figure 2. Fibrillar structure in peeling a pressure-sensitive tape. Note the retraction of fibrils that have separated from the solid. (Reproduced with permission from Ref. 21. Copyright 1969 John Wiley Sons, Inc.)...

Kuhfuss and Jackson s polyester containing 60mol% PHB (COP) [8-10] can serve as a PLC model. Pure COP kept under pressure in a mold shows small fibrillar structures at break (Figure 9.1). This diminishes quickly with an increasing amount of PC and is completely lost in that... 

The tackiness of a specific adhesive is dependent on its ability to bond under light pressure and short contact time, while forming a fibrillar structure upon debonding from the substrate. It is then natural to test tackiness with a quick bonding and debonding test such as those described in the introduction. 

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