A tensioning device for a sheet of material that includes a first ring with protrusions, a second ring, and a shaft. The first ring and the second ring are positioned such that the sheet of material can be clamped between the first ring and the second ring. The shaft has an outer diameter, the outer diameter includes a spiral race such that the protrusions of the first ring follow the spiral race, allowing the first ring and the second ring to displace linearly causing the sheet of material to be stretched. The spiral race includes a plurality of notches that correspond to the protrusions.

An improved device for the uniaxial or biaxial stretching of plastics material portions by means of a stretching frame is characterised among other things by the following features: the stretching frame comprises two pairs of mutually perpendicular guide rails with clips for stretching a plastics material portion, which clips are movable away from or towards each other; the device is constructed such that in addition to the starting position at the beginning of a stretching process and the end position after performing a stretching process, the guide rails and thus the clips seated thereon are additionally movable into a loading position, and the loading position is arranged so that it lies asymmetrically within the stretching frame and is thus closer to at least one longitudinal side of the stretching frame than to the opposite side of the stretching frame.

A film-stretching apparatus in accordance with an embodiment of the present invention includes a stretching furnace which is divided into a plurality of air amount control zones. In a case where the number of the plurality of air amount control zones is seven, a total amount of air to be discharged from, out of the plurality of air amount control zones, three air amount control zones which are located on an entrance side of the stretching furnace is controlled so as to be larger than a total amount of air to be discharged from, out of the plurality of air amount control zones, three air amount control zones which are located on an exit side of the stretching furnace.

The machine (1) includes at least one assistance subassembly (10) having: an endless chain or belt (16); a plurality of thrust members (20) connected to the chain or belt (16) in succession and projecting from the chain or belt (16), and a drive device (21) of this chain or belt (16), several thrust members (20) are brought into the path (3) of the sliders (8) connected to the grippers (4) for gripping the film (F), so that at least one of the thrust members (20) comes to bear against at least one of these sliders (8) and exerts a thrust on this slider to assist the displacement of this slider along the rail (5e) on which this slider moves.

An improved linear-motor-operated conveying system is distinguished, inter alia, by the following features: the conveyed web can be fixed to the nipper part, as a result of which a conveyed web plane is defined, said film plane being arranged at a height with respect to the motor working side of the single linear motor drive or of the more powerful linear motor drive in the case of two linear motor drives, and said height being less than or equal to the length of the secondary parts on the conveying parts; the conveying system comprises either a) only one linear motor drive provided beneath the conveying part, or b) only one linear motor drive provided above the conveying part, or c) one linear motor drive arranged beneath and one arranged above the conveying part, the upper linear motor drive and/or the associated control system being configured in such a manner that the upper linear motor drive can only be operated with a maximum power of 75% in relation to the maximum power of the lower linear motor drive.

Surface-structured polymer bodies in which polymer bodies with dimensions of at least 100 cm.sup.2 are present. The surfaces of the bodies are at least partially covered with at least one nano- to micrometer-thick layer, and the layers are physically and/or chemically coupled to the polymer bodies, and the surface of the polymer bodies with the layers is at least partially deformed. The deformation is periodic within a deformation type and the arrangement of multiple different deformation types on a polymer body is anisotropic or isotropic, and the elastic modulus of the material of the polymer body is less than the elastic modulus of the layer materials.

An improved linear-motor-operated conveying system is distinguished, inter alia, by the following features: the conveyed web can be fixed to the nipper part, as a result of which a conveyed web plane is defined, said film plane being arranged at a height with respect to the motor working side of the single linear motor drive or of the more powerful linear motor drive in the case of two linear motor drives, and said height being less than or equal to the length of the secondary parts on the conveying parts; the conveying system comprises either a) only one linear motor drive provided beneath the conveying part, or b) only one linear motor drive provided above the conveying part, or c) one linear motor drive arranged beneath and one arranged above the conveying part, the upper linear motor drive and/or the associated control system being configured in such a manner that the upper linear motor drive can only be operated with a maximum power of 75% in relation to the maximum power of the lower linear motor drive.

A treatment machine for flexible material webs which can be passed through treatment furnaces is disclosed having at least two successive zones in an extraction direction (A) of the material web, a zone separation device in relation to the extraction direction (A) of the flexible material web. The zone separating device includes at least one air partitioning device (AC) having an injection device (AC-E) which extends transversely to the material web and is designed such that a gaseous fluid flow (S) extending up to the flexible material web is generated above it. The injection device (AC-E) is also designed such that the gaseous fluid flow exiting from the injection device (AC-E) impinges obliquely in the direction of the flexible material web and thus on the material web plane (E) formed by the material web at a blowing angle (?).

An improved stretching system has the possibility of reducing the distance between two successive guide clips, for example. In technical terms, this is solved by using control clips. For example, a control clip can be provided between two successive guide clips and causes the distance between two successive guide clips to be altered by way of a lateral position adjustment by means of a control rail.

Methods and systems for making a film made of dynamically vulcanized thermoplastic elastomeric material are provided herein. The subject methods and systems achieve dimensional stability of an elastic film by applying thermal treatment as part of the film making process and enhance the shrinkage of the film by intentionally with stretching the film while hot and freezing the film in the stretch. The systems and methods are useful in controlling shrinkage of DVA post film extrusion.