Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/49—Phosphorus-containing compounds
  • C08K5/51—Phosphorus bound to oxygen
  • C08K5/52—Phosphorus bound to oxygen only
  • C08K5/521—Esters of phosphoric acids, e.g. of H3PO4
  • C08K5/523—Esters of phosphoric acids, e.g. of H3PO4 with hydroxyaryl compounds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/49—Phosphorus-containing compounds
  • C08K5/51—Phosphorus bound to oxygen
  • C08K5/52—Phosphorus bound to oxygen only
  • C08K5/524—Esters of phosphorous acids, e.g. of H3PO3
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
  • C08L67/04—Polyesters derived from hydroxycarboxylic acids, e.g. lactones

Definitions

• the present invention relates to a method for manufacturing highly oriented and tenacious fibers which comprise a polymer consisting essentially of polypivalolactone (which will hereinafter be referred to merely as polypivalolactone fibers) by melt spinning highly crystalline polypivalolactone and subsequently drawing the spun undrawn fibers.
• polypivalolactone fibers manufactured, according to the method of the present invention, as filaments or staple rfibers covers a wide range from garments to industrial purposes, such as woven fabrics, knitted goods, carpets, nonwoven cloths, felt, web cloth material for synthetic leathers, paddings, papers, filtering cloths and tire cords.
• Example 4 of the specification of said US. patent it is described that by extruding polypivalolactone at a temperature just below the melting point, namely, in the range of from 230 degrees centigrade to 235 degrees centigrade and under a high pressure of 4,000 pounds per square inch and by thereafter manually drawing the extruded fiber to a length four times the original length, a drawn fiber showing an X-ray orientation angle of 17 degrees was obtained.
• Example 5 there is described the acquisition of a [fiber having a high degree of crystallinity, such as a density of 1.20 (24.5 degrees centigrade), by a method similar to the above from polypivalolactone having an intrinsic viscosity (n) of 0.90.
• British Pat. No. 766,347 discloses in Example 7 the fact that, by melt spinning polypivalolactone at a temperature above its melting point, namely, at 285 degrees centigrade, and by drawing the fiber to a length four times the original length at degrees centigrade, a fiber having such properties as are represented by a tensile strength of 1.9 gr./d. and an elongation of 19.9 percent was obtained.
• the method of said US. patent requires an extremely high pressure at the time of spinning and, therefore, it is ditficult to apply this method industrially since there are involved various problems with respect to the feasibility of the operation, the property of the produced fiber and the designing of the manufacturing apparatus, and also from the viewpoint of the maintenance of the apparatus.
• the high density (1.20) of the fiber obtained according to this prior method means that the degree of crystallinity of the polymer constituting the fiber is close to the maximum value which this polymer can attain, and that the heat-setting ability of the fiber is already lost. Accordingly, this shows, for example, the fact that it is impossible to manufacture a crimped fiber of an excellent quality.
• this minimized and stabilized dependency of the rheological property of polypivalolactone on the temperature and the pressure at the time of melting is extremely effective in broadening the range of the appropriate Spinning conditions as well as for improving the efficiency of the operation, the spinnability of the molten polymer at the time of spinning, and improving its detachability from the nozzle, and also in retarding the rapid crystallization of the polymer after the spun fiber is solidified, and further for the improvement of the orientation effected at the time of spinning under draft and during the subsequent drawing step.
• an object of the present invention to provide a polypivalolactone fiber which is highly oriented and which has sufiicient heat-setting ability and which 4 is tenacious, transparent, uniform in quality and greatly useful.
• Another important object of the present invention is to provide an improved industrial method for quite easily manufacturing such a useful fiber by spinning and drawing a polypivalolactone fiber without the need for any special mechanical equipment.
• Still another object of the present invention is to provide an industrial manufacturing method in which desirable manufacturing conditions for obtaining such fiber are specified.
• Yet another object of the present invention is to provide a crimped fiber consisting essentially of polypivalolactone and having a markedly superior extension percentage of crimp and recovery percentage of crimp.
• While the present invention concerns the techniques of melt spinning and drawing a polymer consisting essentially of polypivalolactone, it is to be understood that said polymer is such that it is incorporated uniformly, prior to being subjected to melt extrusion, with a small amount of an additive which consists of at least one organic compound selected from the group consisting of polyethylene, partially oxidized polyethylene, copolymers of ethylene and o fl-ethylenic unsaturated carboxylic acids, polyethylene oxides, parafiinic hydrocarbons, esters of phosphoric acid and esters of phosphorous acid.
• an additive which consists of at least one organic compound selected from the group consisting of polyethylene, partially oxidized polyethylene, copolymers of ethylene and o fl-ethylenic unsaturated carboxylic acids, polyethylene oxides, parafiinic hydrocarbons, esters of phosphoric acid and esters of phosphorous acid.
• polymer consisting essentially of polypivalolactone used in the present invention means polypivalolactone or a copolymer or blend polymer of polypivalolactone as the principal component with other polymer or polymers.
• polypivalolactone which is used in the I present invention means a linear condensation polymer consisting essentially of recurring ester structural units expressed by the formula:
• a copolymer of polypivalolactone means a copolymer which is prepared by copolymerizing the aforesaid polypivalolactone with up to 25 mol. percent of other lactones, such as fi-propiolactone, mot-Cliethylpropiolactone.
• a blend polymer of polypivalolactone as the principal component and of other polymer or polymers is a composition consisting of polypivalolactone or a copolymer of polypivalolactone as the principal component which is blended with other polymer or polymers in an amount essentially not affecting the property of said principal component. It is needless to say that polypivalolactone containing ordinary additives, such as a dye, a pigment and a stabilizer, is also usable.
• the polypivalolactone which is applicable to the present invention have an intrinsic viscosity (17) ranging between 0.7 and 5.5, and preferably in the range between 0.8 and 4.0.
• Polypivalolactone having (1 less than 0.7 is markedly low in fiber-forming ability, and unless it is given an extremely high spinning draft at the time of spinning, the fiber cannot be endowed with utility, nor can it exhibit such excellent properties as are obtained by the present invention.
• a very high value of intrinsic viscosity on the other hand, will result in a restriction of the fiber manufacturing conditions.
• the intrinsic viscosity (1;) is determined by the use of a mixed solvent consisting of six parts of phenol and four parts of orthochloro-phenol and by the employment of a temperature of 30 degrees centigrade and it is calculated from the following equation:
• 0 represents the concentration expressed in grams of polypivalolactone contained in 100 ml. of solution formed by dissolving polypivalolactone in the aforesaid solvent;
• n represents the viscosity of the aforesaid solution, and n repreents the viscosity of said solvent.
• the paraffinic hydrocarbons used in the present invention are alkanes by the general formula C H and having a straight chain structure in which 21514, and include, for example, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nonadecane, eicosane, heneicosane, docosane, tricosane, tetracosane, pentacosane, hexacosane, heptacosane, octacosane, nonacosane, triacontane, dotriacontane, pentatriacontane, tetracontaine, pentacontane, hexacontane, dohexacontane, tetrahexacontane and heptacontane.
• paraffins consisting chiefly of normal parafiins, namely, those commercial parafiins which contain a small amount of such substances as isoparafiin and cycloparaflin besides these normal paraffins, are also usable.
• Normal parafiins having less than 14 carbon atoms invariably have relatively low boiling points. Accordingly, they volatilize at a high temperature, for instance, when they are in the melt-spinning process, and they do not bring forth the desired effect. Therefore, such normal parafiins are not suitable for being used in the method of the present invention.
• Normal paraffins include those occurring in nature, for example, those contained in petroleum oil and also those obtained by synthesis. However, naturally occurring normal paraffins and refined natural normal parafiins are more advantageous from the viewpoint of the price. As for the naturally occurring normal parafiins, those up to heptacontane, which have 70 carbon atoms are well known.
• any paraffiuic hydrocarbons having 14 or more carbon atoms can be used.
• those having lesser molecular weights display a greater effect, and accordingly, the amount of those to be added can be reduced.
• Polyethylenes can also be used effectively in the present invention.
• Polyethylenes having a low mean molecular weight can be regarded in substantially the same light, from the viewpoint of chemical structure, as paraffinic hydrocarbons having high molecular weight.
• Polyethylenes which are used in the present invention include those which are manufactured according to the so-called high pressure process, medium pressure process and low pressure process.
• polyethylenes having a melt index of 20 or more, and preferably 30 or more are effective for the attainment of the objects of the present invention.
• Those polyethylenes having a melt index smaller than the above-mentioned lower limit, namely, those of a higher molecular weight, are poor in the ability of improving the rheological property of poly ivalolactone and are not suited for use in the present invention.
• Partially oxidized polyethylenes which are used in the present invention are such that their methyl radicals located in the end group and side chains have been partly oxidized and converted to carboxylic radicals.
• Copolymers of ethylene and at least one (LfiCthYlCHiC unsaturated 6 carboxylic acid can also be effectively used in the present invention.
• Such carboxylic acids include, for example, acrylic acids, methacrylic acid, itaconic acid, maleic acid, fumaric acid, aconitic acid, citraconic acid and mesaconic acid. These copolymers possess chemical structures which are similar to those of the partially oxidized polyethylene.
• Such ethylene copolymers can be obtained by copolymerizing ethylene and one or more of said u,n-ethylenic monomers.
• Various methods for use in the synthesis of such olefin copolymers are known from a number of literature disclosures.
• One example of the preferred methods comprises introducing a mixture of two monomers, such as those mentioned above, together with a free radical polymerization initiating agent, such as a peroxide, into a polymerizing zone held under a high pressure between 10 and 3,000 atmospheres and at a high temperature between degrees centigrade and 300 degrees centigrade.
• Polymerization may be carried out by the use of a solvent, such as water or benzene, which is inactive toward the reaction system, or it may be performed essentially as bulk polymerization.
• a solvent such as water or benzene
• Polyethylene oxide which is a completely different form of partially oxidized polyethylene, can also be satisfactorily used as an additive in the present invention.
• Polyethylene oxide can be readily obtained by subjecting an ethylene oxide to ring opening polymerization by the use of a Friedel-Crafts type catalyst or an alkaline or acidic catalyst.
• those having a molecular weight of about 600 or more are particularly suitable for the purposes of the present invention.
• esters of phosphoric acid and phosphorous acid can also be used effectively as an additive in the present invention.
• the suitable range of the amount of the foregoing additives to be used is between 0.1 and 10.0 percent by weight, and preferably, between 1.0 and 6.0 percent by weight of the total weight of the composition comprising a polymer consisting essentially of polypivalolactone and the additives.
• Those additives having a low molecular weight display a sufiicient effect by being used in a small amount.
• the amount added is less than 0.1 percent by weight, however, it does not bring about a substantial effect on the improvement in the drawability of the spun fiber in the steps subsequent to the first step, as compared with the instance where no additive is used.
• the amount is in excess of 10.0 percent by weight, on the other hand, the result will be a reduced spinnability which will be accompanied by a reduction in the uniformity of the size of the final fiber.
• the aforesaid additives are incorporated, either independently or as a mixture of two or more of them, with polypivalolactone after the completion of the polymerization of polypivalolactone and are mixed thoroughly therewith while being stirred so that the additive may be dispersed uniformly.
• Polypivalolactone containing such additive in the state of a uniform dispersion is transferred to the first step, namely, the melt-spinning step either directly or after 'being shaped into granules or chips.
• such polypivalolactone When required, such polypivalolactone may be melted to effect a thorough mingling of the additive in the polypivalolactone and then made into chips before being transferred to the spinning step.
• the aforesaid additive which has been incorporated 'with polypivalolactone be present therein in such a state that the additive is uniformly dispersed or mingled in the polypivalolactone by a mechanical opera tion, such as mixing by stirring, 'while in the melted state.
• This mixing by stirirng may be carried out by means of a screw housed in an apparatus such as a melt extruder or by means of a pump or like means.
• the aforesaid additive which is thus added and dis persed in polypivalolactone, retains its state of being molten, mingled and dispersed in the molten polypivalolactone for an extended period of time.
• the additive contained in the aforesaid form in polypivalolactone displays the following named various excellent effects in association with the subsequent steps, without separating from the mixed state under normal melt-spinning conditions and without affecting in any way the desirable chemi cal as well as physical properties of polypivalolactone:
• the polypivalolactone which has been mixed uniformly with an additive can be spun and drawn easily by the use of a known melt-spinning and take-up apparatus and drawing apparatus, without requiring any special mechanical equipment.
• polypivalolactone which has been melted in a known melt-spinning apparatus is extruded in fiber form through an orifice of a spinneret.
• the temperature employed in this melt-spinning step is in the range between 240 degrees Centigrade and 310 degrees centigrade.
• the fluidity of a polymer increases with the elevation of the temperature, resulting in an improved spinnability.
• the temperature of the polypivalolactone exceeds 280 degrees Centigrade, however, it tends to become difiicult to control the melt viscosity at the time of spinning and also the spinning conditions due to various reasons, including thermal decomposition of the polymer.
• melt-spinning apparatus any known apparatus, such as a grid melter and a screw extruder-type apparatus, may be employed as desired. In case it is desired to perform melt spinning at a relatively low melt-spinning temperature,
• a screw extruder is advantageously used.
• the diameter of the orifice of the spinneret there is no particular restriction thereon.
• the term spinning deformation ratio herein referred to means the ratio of the cross-sectional area of the polymer at the moment of extrusion through the orifice of the spinneret to the cross-sectional area of the undrawn fiber after being quenched and solidified, and it has a close relationship with the degree of orientation of the undrawn fiber.
• polypivalolactone polymers have the shortcoming that those with a greater molecular weight have a higher melt viscosity and accordingly result in a reduced efficiency of operation, it is to be noted that, because the spinnability is markedly improved by the admixture of an additive, a polypivalolactone polymer having a markedly high molecular weight can be easily spun.
• the polypivalolactone which is melt extruded from the orifices of the spinneret in the first step is immediately given the required amount of high draft in the second step.
• it is important to carefully take into consideration the characteristics of the polymer namely, that it is of a high degree of crystallinity and that its crystal is fairly rigid.
• the crystal of polypivalolactone being considerably rigid, the degree of its crystallinity is not at all reduced even when the temperature is elevated to the vicinity of its melting point (240 degrees Centigrade), and thus, polypivalolactone has a very narrow softening range.
• the polymer extruded from the orifice of a spinneret have a stress imparted thereto while it is still in the molten or plasticized state, or in other words, while it is at a temperature higher than 10 degrees centigrade below the melting point and more particularly while it is in the temperature range between 310 degrees Centigrade and 230 degrees centigrade, and that the polymer be thus transferred to such a drawable condition as is accompanied by the orientation of a high degree.
• the temperature falls to a temperature lower than that of the narrow softening range during the spinning step, there takes place a rapid crystal growth and the molten polypivalolactone is already in an essentially undrawable condition which is never seen in other molten polymers.
• the taken-up fiber fails to acquire the effect of the drawing which is carried out in the next drawing step.
• the polymer is given such a spinning deformation ratio as will cause the polymer to possess, during spinning, a fiber structure which is oriented beyond the minimum value required ordinarily.
• the spinning deformation ratio which brings about such a fiber structure can be obtained by appropriately selecting the individual spinning conditions, and especially, the size of the orifice, the rate of extrusion, the take-up speed and the spinning atmosphere around the spinneret, and also by the application of a high draft. It is to be noted that this spinning atmosphere does not require any such strict control of the temperature or humidity of the atmosphere as is necessary in the spinning of nylon or polyethylene terephthalate.
• the spinning deformation ratio has to be determined by taking into consideration the fact that the molecular weight of polypivalolactone is very closely associated with the rheological property of polypivalolactone when the latter is melted and also with the spinning conditions employed.
• the workability in the spinning process is markedly improved as is represented by the improved spinnability of the molten polymer and the improved detachability of the molten polymer from the nozzle, it is possibleto obtain a desired fiber under such conditions that the spinning deformation ratio is set at a relatively small value.
• the effect of increasing the value of A can be obtained also by the employment of a reduced spinning pressure and also by the use of a larger size orifice of the spinneret and further by increasing the take-up speed.
• the spinning temperature exceeds 310 degrees centigrade, the control of the melt viscosity at the time of spinning and the control of the spinning conditions become diflicult, owing to the reasons, including thermal decomposition, as have been previously described.
• the employment of the additive in the present invention brings forth such effects that the fluidity of the polymer at the time of its being melted is increased, that the spinnability of the molten polymer is markedly enhanced and that the detachability of the molten polymer from the nozzle is improved.
• the employment of the additive is further useful from the aspect of uniformizing the size of the obtained fiber and, therefore, this is particularly advantageous in the spinning of a polypivalolactone having such a high molecular weight as has been described above.
• a fiber which is given a required spinning deformation ratio in the second step is then transferred to the third step.
• What is the most unusual of the physical properties of polypivalolactone is that this polymer crystallizes rapidly as time passes and that it attains an extremely high degree of crystallinity as is pointed out in the aforementioned paper of R. Thiebaut et al. and also in the French Patent No. 1,231,163.
• Such changes in the undrawn fiber due to the lapse of time not only hampers the orientation of the molecular chains at the time the fiber is drawn and constitutes the cause for a brittle fiber, but also causes numerous cracks to develop in the direction perpendicular to the direction in which the fiber is drawn, and may bring about the formation of an opaque fiber.
• a fiber which is produced by melt spinning after said polymer has been admixed with the aforesaid additive possesses an ability to reduce the adverse effect caused by the lapse of time, when compared with a fiber obtained from a polymer not containing an additive and spun under the same spinning conditions.
• additives even those having the highest density, have a melting point which is lower by at least 1'00 degrees centigrade than that of polypivalolactone, they provide an appropriate lubricating effect acting between the molecular chains of polypivalolactone, and that the degree of orientation of the undrawn fibers obtained from polypivalolactone containing such additives is always higher than the degree of orientation of the undrawn fibers obtained from polypivalolactone not containing additives and that the use of the additives is effective in the improvement of the orientation of fibers.
• the difficulties which are otherwise encountered in the first and the second steps can be markedly improved by the employment of the additives.
• this employment of additives serves to provide a very high enhancement of the effect of orientation of the spun fiber in the third or the drawing step and contributes to the improvement in the tensile strength and elongation of the obtained drawn fiber.
• the desired object can be attained by conducting the drawing at a temperature lower than that required for the drawing of a fiber spun from the polymer not containing an additive.
• the drawing operation can be performed at such low temperatures as are defined by the following Equations 2 and 3:
• T;-765.2R +420R The melting point of said additive wherein: R represents the degree of orientation of an undrawn fiber.
• the draw ratio is appropriately determined to be within the range of value between 1.5 and 10.0 so as to be in accord with the excellent elongation property of the individual undrawn fibers.
• the value of the spinning deformation ratio A in the second step has to be taken into account in the determination of the proper draw rate. Since the degree of orientation of the undrawn fiber increases with an increase in the value of A, it is possible to carry out the third step at a reduced draw rate, and therefore, the final fiber property can be stabilized by a small drawing operation in the order of merely adjusting the residual degree of elongation of the undrawn fiber.
• the fiber obtained according to the method of the present invention exhibits a markedly improved fiber property as compared with known fibers, and has an adequate degree of crystallinity, and shows a very small shrinkage in boiling water, and possesses a stabilized fiber property.
• the one which is very important from the viewpoint of developing the utility of the fiber is the heat-setting ability of such fiber.
• the density value of 1.20 (corresponding to the degree of crystallinity of 78.8 percent) of the fiber described in U.S. Pat. No. 2,658,055, as is quoted in Table 3 is close to the maximum degree of crystallinity which this polymer can attain, and this leads to the assumption that the fiber has already lost its heat-setting ability.
• the fiber manufactured according to the method of the present invention shows an appropriate density value of 1.17 or less (corresponding to the degree of crystallinity of 58 percent or less), leaving a difference of 20 percent or more in the degree of crystallinity from that of the fiber of the prior art. Therefore, this means that the fiber of the present invention has a sufficient heat-setting ability.
• an excellent crimped yarn can be manufactured from the fibers of the present invention by utilizing this heatsetting ability of the fibers and by the use of a known mechanical crimping method, such as the twisting-settinguntwisting method, false twisting method and the stuff-inbox method, and also, that the extension percentage of crimp and the recovery percentage of crimp of the obtained crimped fiber can be markedly superior in conjunction with the intensive degree of orientation, the degree of crystallinity and the Youngs modulus of the fiber.
• the performance of the method of the present invention does not require any special machinery or equipment, but any known apparatuses, such as conventional melt-spinning apparatus and drawing apparatus can be utilized without requiring any modification.
• the degree of orientation R which is used in the description of the following embodiments is of a value calculated by first determining the azimuthal X-ray diffraction pattern of the peak at 15.4 degrees, 20, and then 12 applying the half width B thereof to the following equation:
• Example 1 To batches of polypivalolactone having an intrinsic viscosity n of 1.5 were added, separately, 0.2 percent, 2 percent, 6 percent and 10 percent by weight of parafiin (made by Wako Jun-yaku C0.) composed principally of. pentatriacontane and having melting points ranging from 70 degrees Centigrade to 73 degrees centigrade. The resulting mixtures were melted by heating. The molten mixtures were stirred so that the additives were thoroughly mixed with the polymer. The melt viscosity of the resulting mixtures was measured. This measurement was conducted by the use of Koka-type flow tester (made by Shimazu Seisakusho) and under the following conditions.
• Koka-type flow tester made by Shimazu Seisakusho
• the molten mixtures were extruded at 250 degrees centigrade and under a pressure of 10 kg/cm. through nozzles 1 mm. in length and 0.3 mm. in orifice diameter.
• the extrusion rate Q (cc.) per unit time was measured. From the obtained extrusion rate the apparent melt viscosity 1 (poise) was calculated by the following equation:
• r represents the radius (cm.) of the nozzle.
• P represents the pressure (dyne/cmF).
• L represents the length (cm.) of the nozzle.
• Q represents the extrusion rate (cc./sec.).
• Example 2 Using a spinneret equipped with 10 orifices, each being 0.5 mm. in diameter, molten polypivalolactone having an intrinsic viscosity of 1.45 was extruded at a meltspinning temperature of 270 degrees centigrade into an atmosphere held at 22 degrees centigrade and at a relative humidity of percent.
• Fiber size fluctuation pereentage 100 Swipe-ow TABLE 4 Residual elon- Draw Draw Tensile Elon- Knot Loop Sample gation temperture ratio strength gation strength strength Number R ercen C (X) (g /d) (perce (g -I (e Appearance of fi 1 0,63 10 60 Operation not feasible because of frequent breakage of fiber. 353 4. 5 1. 5 32 1. 2 2. 2 Excellent, transparent. 295 3. 5 1.4 26 1. 2. 0 White opacity with cracks. 610 6. 5. 0 28 4. 3 9.1 Excellent, transparent.
• n the total number of measurements taken.
• Fibers containing paraffin exhibited a markedly improved draw ratio, with the result that a smooth drawing operation was accomplished with no appreciable development of cracks in the obtained fibers, and the drawn fibers were transparent.
• the increased draw ratio of the fibers due to the addition of parafiin was extremely effective for the improvement of the orientation and the tenacity of the fiber, and the effect of the use of this additive was markedly apparent in each of the characteristics of tensile strength, knot strength and loop strength.
• Example 3 To samples of polypivalolactone having an instrinsic viscosity (7 of 1.5 were admixed, separately, five percent and 10 percent by weight of polyethylene (Sumikathen G-806, made by Sumitomo Chemical Co., Ltd.) having a melt index of 50, and also to a separate sample 10 percent by weight of partially oxidized polyethylene (AC629, made by Allied Chemical Co. of U.S.A.) with melting point of 97 degrees centigrade and molecular weight of 2,000. The resulting mixtures were melted by heating, respectively, followed by thorough mixing by stirring. The melt viscosity of the resulting mixtures was measured in the same manner as was described in Example 1 and the apparent melt viscosity (1 (poise) was calculated from the extrusion rate. The result of the measurement is shown in the following Table 5:
• Example 4 made by Eastman Co. of USA. having a molecular weight of 1,500 and a melting point of 92 degrees centigrade to said polypivalolactone.
• the mixtures were subjected, respectively, to spinning and drawing in the same manner as that described above, and the obtained fibers were designated as the Fibers (III) and (IV) of the Using polypivalolactone having an intrinsic viscosity present invention, respectively.
• Their fiber properties are (1 of 1.21, this polymer was melt spun through an exshown in the following Table 7:
• truder under the following conditions, namely, at a spinp 6 ning temperature of 260 degrees centigrade and by the A copolymer of ethylene and maleic acid was prepared use of a spinneret having 20 orifices each having a diamby the following process. Methyl alcohol and di-terteter of 0.3 mm. and at a spinning deformation ratio of butyl-peroxide were mixed together at the rate of 15 300. Thus, undrawn fibers were obtained. Control fibers parts and 10 parts by weight per hour, respectively. Into 1 were prepared by drawing these d fib o this mixture was dissolved maleic acid at the rate of 20 3.5 times the original length at 60 degrees Centigrade.
• the fibers thus obtained were designated percent by Weight f the Obtained ethylene t Fibers and P the Preseht ihvehhohi respec' polymer was added to polypivalolactone having an iny
• the h p p f 0f thfise three klhds 0f fibers trinsic viscosity (1;) of 1.03, and the mixture was melt spun are shown in the following Table 6: 40 using a heat grid-type melt-spinning apparatus and under TABLE 6 Undrawn fiber Drawn fiber Residual Tensile Elon- Knot Loop Young's Fiber size elongation strength gation strength strength modulus fluctuation Sample R (percent) (gr./d.) (percent) (gr./d.) (gr./d.) (kg/cm?) (percent) Control fiber (I) 0. 71 280 1.6 12 1.0 2.5 455 15.9 Fiber (1) of the present invention. 0.80 560 6.4 37.
• Example 5 the conditions, i.e., by the use of a spinneret having 20 I orifices each having a diameter of 0.35 mm. at a spin- Uslhg Polyplvalolactohe havlhg ah lhtllhslc vlscoslty ning temperature of 265 degrees Centigrade and at the l) of -h thfi P y Was S131111 under the follow" spinning deformation ratio of 450, to produce undrawn g cohdltlohs, at a Splhhlhg temperature of 275 fibers.
• Fibers obtained in exactly the same fibers were o taln d- T fibers h f i y dfaWlhg manner as that described above with the exception that said undrawn fibers to 4.0 times their original length at h h l copolymer was not dd d t th olymer IOOfh temperature were Used 35 Control fiber D- Next, were designated as the control fiber (III).
• the fiber propa mixture which was pr par d by addi g 55 p c y erties of these two kinds of fibers are shown in the folweight of polyethylene (with a molecular weight of lowing Table 8:
• Example 7 to the aforesaid polypivalolactone prior to being spun, and another mixture prepared by adding 1.5 percent by The changes of elongability with lapse of time of the weight of partially oxidized polyethylene (Epolene LVE, respective undrawn fibers obtained in Examples 4 through 6, measured from the time immediately after being spun are shown in the following Table 9:
• Control fiber (I) 280 10-20 Control fiber (I 310 245 230 205 Control fiber (III) 270 1 l Fiber (1) of the present invention 560 540 520 515 Fiber (II) of the present invention” 620 605 595 595 Fiber (III) of the present invention- 630 610 610 600 Fiber (IV) of the present invention- 590 575 575 575 Fiber (V) of the present invention 580 560 530 530 1 Or less.
• control fibers showed a sharp reduction in elongability and became brittle due to the rapid crystallization caused by the lapse of time.
• the fibers of the present invention invariably showed a minimized effect of the changes due to lapse of time and the crystallization velocity was retarded. It has been proved that the fibers of the present invention can retain drawability for an extended period of time.
• Example 8 Polypivalolactones having an intrinsic viscosity (1;) of 1.10, 1.45 and 1.72, respectively, were extruded into an atmosphere held at 22 degrees centigrade and a relative humidity of 65 percent, using a spinneret having 10 orifices each having a diameter of 0.5 mm., and at a meltspinning temperature in the range between 260 degrees centigrade and 280 degrees centigrade.
• the value of the spinning deformation ratio A was varied by changing the take-up speed during winding the filaments extruded under the foregoing conditions, to thereby produce undrawn fibers having various degrees of orientation R.
• the relationship between this R and the tensile strength (meas ured based on JIS-L-1073) is shown in the following Table 10:
• the paraflin which is added, serves to markedly improve the rheological property when the polymer is spun and to greatly enhance the spinnability and also the detachability of molten polymer from the nozzle, and furthermore, it minimizes the fiber size fluctuation of the obtained undrawn fibers.
• the marked advantages of the use of parafiin are observed in both the operation and the fiber property.
• the improved rheological property further permits the spinning to be easily carried out even at a low temperature, and, as is shown in the following Table 12, it brings forth an effect that a reduction in the viscosity of polymer can be arrested.
• Example 9 The result of the measurements of the tenacity of the fibers resulting from drawing is shown in the following Table 14:
• Table 16 also shows the result of the study on the effect given by the draw temperature.
• Sample f and Sample g it is noted that in case the amount of polyethylene added is in excess of 10.0 percent by weight which is defined by the present invention, the drawing does not fully contribute to the improvement of orientation.
• EXAMPLE 11 To polypivalolactone powder having an intrinsic viscosity (1 of 1.22 was added 2.8 percent by weight of partially oxidized polyethylene (AC-629, made by Allied Chemical Co.) having -a molecular weight of 2,000 and a melting point of 97 degrees centigrade, and thereafter the mixture was thoroughly mixed together by a V-type blender for one hour. The resulting mixture was extruded through a spinneret having six orifices each having a diameter of three mm., at the temperature of 260 degrees centigrade in the nozzle, and of 230 degrees centigrade at a site below the hopper, by using a screw-type melt extruder.
• AC-629 partially oxidized polyethylene
• the molten polymer extruded from the nozzles at the rate of 80 gr./min. was passed through quenching rollers of 30 cm. in diameter and thereafter was left to drop downward by its own weight and to solidify. Then, the solidified polymer was cut into lengths of four mm. by a cutter designed for the manufacture of chips to thereby manufacture polypivalolactone chips. These chips were used as the charge stock for the spinning. In carrying out the melt spinning of this sample, it was required to set the spinning deformation ratio at 160 or more from the definition made by the conditional Equation 1 described previously in this specification.
• the spinning deformation ratio which is applied to this polymer having said intrinsic viscosity was required to be 280 or more.
• the undrawn fibers were drawn to six times the original length at 60 degrees centigrade, and as a result, tenacious drawn fibers having an excellent fiber property, i.e., having a monofilament size of 1.2 d., a tensile strength of 5.2 gr./d., an elongation of 38 percent, a Youngs modulus of 430 kg./m1n. a knot strength of 4.8 gr./d., a loop strength of 9.3 gr./d. and a shrinkage in boiling water of 2.7 percent, were manufactured.
• Example 13 A copolymer of ethylene and methacrylic acid having a copolymeric mol ratio of 97:3 was prepared in the same manner as that in Example 6. To polypivalolactone having an intrinsic viscosity (1;) of 1.70 was added three percent by weight of the obtained copolymer, and the mixture was shaped into chips.
• Example 14 To polypivalolactone having an intrinsic viscosity (7;) of 2.0 was added 3.5 percent by weight of polyethylene oxide having an average molecular weight of 6,000. In a manner similar to that in Example 11, the mixture was shaped into chips which were melt extruded by the use of a screw extruder. Under the spinning conditions, i.e., by the use of a spinneret having 18 orifices each having a diameter of 0.25 mm, at a spinning temperature of 275 degrees centigrade, at an extrusion rate of 12.6 gr./min., at a take-up speed of 400 m./min.
• Example 1 To powder polypivalolactone having an intrinsic viscosity (1 of 2.40 was added 3.0 percent by weight of polyethylene glycol having a molecular weight of about 2,000. In a manner similar to that employed in Example 11 the mixture was thoroughly blended together and then made into chips. Using a screw-type melt extruder, and under the conditions, i.e., by the use of a spinneret having 12 orifices each having a diameter of 0.2 mm., at a spinning temperature of 277 degrees centigrade, at an extrusion rate of 9.0 gr./min., at a take-up speed of 670 m./min.
• the resulting undrawn fibers were cold drawn at a room temperature to 7.5 times the original length, and tenacious drawn fibers having a monofilament size of 1.33 d., a tensile strength of 8.2 gr./d., an elongation of percent, a Youngs modulus of 650 kg./mm. a knot strength of 7.5 gr./d. and a loop strength of 13.4 gr./d., were obtained.
• Example 16 To powder polypivalolactone having an intrinsic viscosity (1;) of 2.00 was added a solution of benzene having a molecular weight of about 500 and a melting point of 70 degrees centigrade in such manner that the pure parafi'in content in said polymer was 5.5 percent by weight. While heating and stirring the mixture, ben- Zene was evaporated therefrom. After the remaining substance was thoroughly dried up, it was melt spun using the spinning apparatus employed in Example 8. Under the spinning conditions, i.e., by the use of a spinneret having one orifice of 0.2 mm.
• a tenacious drawn fiber having a monofilament size of 1.5 d., a tensile strength of 7.0 gr./d., an elongation of 30 percent, a Youngs modulus of 525 kg./mm. a knot strength of 6.6 gr./d. and a loop strength of 11.8 gr./d., was obtained.
• v7 intrinsic viscosity
• This undrawn fiber was then drawn at a room temperature to 5.1 times the original length, and thus, a tenacious and excellently uniform filament having a fiber size of 14.9 d., a fiber size fluctuation of 6.2 percent, a tensile strength of 8.4 gr./d., an elongation of 26 percent, a Youngs modulus of 680 kg./mm. a knot strength of 8.1 gr./d. and a loop strength of 15.9 gr./d., was obtained.
• Example 18 To polypivalolactone having an intrinsic viscosity '1; of 1.6 was added 2.5 percent by weight of trioctadecyl phosphite, and in the manner described in Example 11, chips were produced. From the Equation 1, the spinning deformation ratio required for the melt spinning of said chips was 63 or more. Using a heat grid-type melt-spinning apparatus, and under the conditions, i.e., by the use of a spin-neret having 18 orifices each having a diameter of 0.4 mm, at a spinning temperature of 275 degrees centigrade, at a take-up speed of 500 m./min.
• the chips were melt spun into an atmosphere held at 20 degrees centigrade and a relative humidity of percent.
• the undrawn fibers ' were drawn at room temperature to 3.7 times the original length, and thus, tenacious filaments having a size of 70 d./ 18 fil., a tensile strength of 6.1 gr./d., an elongation of 35 percent, a Youngs modulus of 520 kg/mm. and a shrinkage in boiling water of 3.0 percent were obtained.
• Example 19 The respective drawn fibers obtained in Examples 11 through 13 were made into crimped fibers. Specifically, a part of them was subjected to a crimping process by the use of a false twisting machine of 08-3 type made by Earnest Scrugg Co. (England), under the conditions of processing which were: the speed of the feed-in roller being 63.5 m./min., the surface temperature of the heater being 210 degrees centigrade, the revolution of the spindle being 200,000 rpm. and the speed of the delivery roller being 61 m./min. The sample thus obtained was designated as Sample A.
• a drawn, tenacious polypivalolactone fiber having a maximum density of 1.17 and a heat-setting ability which is formed of a composition comprising a polymer consisting essentially of polypivalolactone and a small amount of a least one organic compound selected from the group consisting of polyethylene, partially oxidized polyethylene, copolymers of ethylene and u,,B-6thylBI1iC unsaturated carboxylic acids, polyethylene oxide having a molecular weight of at least 600, and an alkane, C H wherein r2514, said organic compound being uniformly distributed in said polymer.
• a fiber according to claim 1, wherein said organic compound is a polyethylene having a melt index of at least 20.
• a fiber according to claim 1, wherein said organic compound is a polyethylene having a melt index of at least 30.
• a fiber according to claim 1, wherein said organic compound is selected from the group consisting of at least one copolymer of ethylene and at least one a,fi-ethylenic unsaturated carboxylic acid selected from the group con sisting of acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, aconitic acid, citraconic acid and mesaconic acid.
• a fiber according to claim 1, wherein said organic compound is a polyethylene oxide having a molecular weight of at least 600.
• n 2n+2 wherein: ngl4.

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• 1967
  • 1967-07-27 US US656350A patent/US3575907A/en not_active Expired - Lifetime
  • 1967-07-28 CH CH1075167D patent/CH1075167A4/xx unknown
  • 1967-07-28 NL NL6710509A patent/NL6710509A/xx unknown
  • 1967-07-28 CH CH1075167A patent/CH510760A/de not_active IP Right Cessation
  • 1967-07-28 CH CH941368A patent/CH490523A/de not_active IP Right Cessation
  • 1967-07-28 BE BE702040D patent/BE702040A/xx unknown
  • 1967-07-29 DE DE19671669483 patent/DE1669483A1/de active Pending
  • 1967-07-31 GB GB35017/67A patent/GB1191644A/en not_active Expired
• 1970
  • 1970-06-01 US US54052A patent/US3657178A/en not_active Expired - Lifetime

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