《PLASTICS PROGRESS 1961》

POLYOLEFINES Ⅰ1

TECHNICAL DEVELOPMENTS IN OLEFINE POLYMERS＆H．C．Rains1

High pressure polythene3

Low pressure polythene6

Polypropylene8

Polymers of higher olefines13

DISCUSSION ON POLYOLEFINES Ⅰ15

POLYOLEFINES Ⅱ19

HIGH DENSITY POLYTHENE AND POLYPROPYLENE IN EUROPE＆Gerd H．Bausback19

Low pressure processes19

Development of high density polythene20

Applications for high density polythene21

Polypropylene developments22

Polypropylene applications23

Conclusions24

WORLDWIDE COMMERCIAL ASPECTS OF LOW DENSITY POLYTHENE＆W．A．Woodcock25

Major applications26

Packaging film26

Moulded products26

Extruded products26

Misapplication of plastics products27

Overlapping of uses27

Development and improvement27

DISCUSSION ON POLYOLEFINES Ⅱ29

POLYSTYRENES33

A SURVEY OF MATERIAL DEVELOPMENTS IN STYRENES＆Gordon B．Thayer and Freeman R．Lehman33

Range of＂plain＂polystyrenes33

Easy flow grades34

Improved toughness34

Heat resistance34

Light resistance35

Moulding and extrusion characteristics39

Rubber modified polystyrenes39

Styrene copolymers42

Expanded polystyrenes43

Polystyrene films45

POLYSTYRENES IN THE NINETEEN SIXTIES＆V．Norman Luke47

Consumption and prices47

Grades and applications49

Production resources51

Population factors52

Prices53

Product performance54

Insulating board55

Packaging applications55

New polymers56

Improvement in properties57

Capital availability58

Future trends59

DISCUSSION ON POLYSTYRENES62

VINYLS65

TECHNICAL DEVELOPMENTS IN THE FIELD OF P．V．C．＆J．J．P．Staudinger65

Structure of p．v．c．66

Stereoregular p．v．c．67

Temperature effects on structure68

Structural effects on properties69

Graft copolymerization70

Polymer blends71

Chemical modification of polymers73

After-chlorination of p．v．c．73

THE COMMERCIAL DEVELOPMENT OF POLYVINYL CHLORIDE＆D．G．Owen77

DISCUSSION ON VINYLS87

PROCESSING THERMOPLASTICS Ⅰ91

DEVELOPMENTS IN SINGLE-SCREW INJECTION MOULDING＆A．Klsine-Albers91

High temperature injection moulding92

Equipment and controls96

Processing of powders99

Filling the mould100

Flow moulding100

BOTTLE BLOWING TECHNIQUES＆J．F．E．Adams105

Processce105

Injection/blowing106

Extrusion/blowing106

Manufacturing techniques107

Mould design107

Mould alignment108

Mould venting109

Blowing position109

Welding110

Automatic handling111

Extrusion111

Bottle finish112

Extrusion heads121

Relaxation121

Printing123

Conclusion125

DISCUSSION ON PROCESSING THERMOPLASTICS Ⅰ127

PROCESSING THERMOPLASTICS Ⅱ131

THE PRESENT STATE AND DEVELOPMENT OF EXTRUSION PRACTICE＆G．P．M．Schenkel131

Vented extruders133

Extruders feeding calenders134

Extrusion of p．v．c．sheet and film136

Extrusion of special polyolefine films143

Extrusion of products with large dimensions144

Multiple extrusion of small-section products145

Extrusion of plastics nets145

CURRENT ADVANCES IN FILM MANUFACTURING EQUIPMENT＆David Grant151

Tubular film plant152

Extruder152

Die design152

Cooling ring161

Film haul-off163

Film winders163

Limitations and developments in tubular film manufacture166

Gauge control166

Output limitations167

Flat film plant168

Extrusion dies168

Water quench system170

Casting roll system171

Haul-off and winding174

Limitation and developments in flat film manufacture175

Tubular versus flat polythene film176

Other thermoplastic films177

Conclusions177

DISCUSSION ON PROCESSING THERMOPLASTICS Ⅱ179