阅读说明：本技术 防弹头盔壳体 (Bulletproof helmet shell ) 是由 约翰娜·范埃尔伯格 哈姆·范德威尔夫 鲁洛夫·梅里森 乌尔里希·海塞尔 劳尔·马塞里诺·佩雷 于 2018-12-14 设计创作，主要内容包括：本发明涉及一种用于制造防弹弯曲成形制品的方法,所述方法包括形成多个复合片材的叠层,在介于80℃至150℃之间的温度和介于10巴与400巴之间的压力下压制包含所述复合片材的所述叠层至少5分钟以获得弯曲成形制品,将压实的叠层冷却至低于80℃的温度同时维持大于10巴的压力,从所述冷却的弯曲成形制品释放压力；其中所述复合片材包含单向排列的高韧性聚乙烯纤维和包含聚乙烯树脂的基质,所述聚乙烯树脂是乙烯的均聚物或共聚物,具有当根据ISO 1183测量时在介于870kg/m<Sup>3</Sup>至980kg/m<Sup>3</Sup>之间的密度和当根据ASTM 1238B-13在190℃的温度和21.6kg的重量下测量时在介于0.5g/10min与50g/10min之间的熔体流动指数。(The present invention relates to a process for manufacturing a ballistic resistant curved shaped article, said process comprising forming a stack of a plurality of composite sheets, pressing said stack comprising said composite sheets at a temperature between 80 ℃ and 150 ℃ and a pressure between 10 bar and 400 bar for at least 5 minutes to obtain a curved shaped article, cooling the compacted stack to a temperature below 80 ℃ while maintaining a pressure above 10 bar, releasing the pressure from said cooled curved shaped article; wherein the composite sheet comprises unidirectionally arranged high tenacity polymersEthylene fibres and a matrix comprising a polyethylene resin which is a homopolymer or copolymer of ethylene having a molecular weight of between 870kg/m when measured according to ISO1183 3 To 980kg/m 3 A density of between 0.5g/10min and 50g/10min when measured at a temperature of 190 ℃ and a weight of 21.6kg according to ASTM 1238B-13.)

1. A method for manufacturing a ballistic resistant curved shaped article, the method comprising:

-forming a stack of a plurality of composite sheets;

-pressing the stack comprising the composite sheet at a temperature between 80 ℃ and 150 ℃ and a pressure between 10 and 400 bar for at least 5 minutes to obtain a bent shaped article;

-cooling the compacted stack to a temperature below 80 ℃ while maintaining a pressure of more than 10 bar;

-releasing the pressure from the cooled curved shaped article;

wherein the composite sheet comprises unidirectionally arranged high tenacity polyethylene fibers and a matrix comprising a polyethylene resin which is a homopolymer or a copolymer of ethylene having a tenacity of between 870kg/m when measured according to ISO1183³To 980kg/m³A density of between 0.5g/10min and 50g/10min when measured at a temperature of 190 ℃ and a weight of 21.6kg according to ASTM 1238B-13.

2. The method of claim 1, wherein the composite sheet comprises from 2 to 25 wt% polyethylene resin based on the total weight of the composite sheet.

3. The method of any one of claims 1 and 2, wherein the polyethylene resin has a tensile modulus at 25 ℃ of between 50Mpa and 500Mpa and a tensile modulus at 110 ℃ of between 0.1Mpa and 10Mpa, determined according to ASTM D5026 at a frequency of 1Hz with a heating rate of 5 ℃.

4. The method of any one of claims 1 to 3, wherein the polyethylene resin comprises at least 90 mol% of monomer units derived from ethylene.

5. The method of any one of claims 1 to 4, wherein the polyethylene resin is an at least partially neutralized ethylene copolymer further comprising monomer units derived from at least one unsaturated carboxylic acid.

6. Ballistic resistant curved shaped article obtainable by the process according to any one of claims 1 to 5.

7. A ballistic resistant curved shaped article comprising a plurality of molded composite sheets comprising a unidirectional array of Ultra High Molecular Weight Polyethylene (UHMWPE) fibers and a matrix comprising a polyethylene resin, said polyethylene resin being a homopolymer or copolymer of ethylene having a weight average molecular weight of between 870kg/m when measured according to ISO1183³To 980kg/m³(ii) a density of between 0.5g/10min and 50g/10min when measured at 190 ℃ and a weight of 21.6kg according to ASTM 1238B-13; wherein the antiballistic curved shaped article has less than 8.0kg/m²And a V according to MIL-STD-662f (1997) of more than 750m/s₅₀17 grain FSP.

8. Ballistic resistant curved shaped article according to claim 7, wherein the average thickness of the ballistic resistant curved shaped article is less than 8 mm.

9. Ballistic resistant curved shaped article according to any one of claims 7 or 8, wherein the ballistic resistant curved shaped article has a backface signature of less than 20mm when measured according to the NIJ 0106019 mmFMJ RN Remmington threat.

10. Ballistic resistant curved shaped article according to any one of claims 7 to 9, further comprising at least one layer comprising carbon fibers.

11. Ballistic resistant curved shaped article according to any one of claims 7 to 10, further comprising a coating comprising polyurea on the outer surface.

12. Ballistic resistant curved shaped article according to any one of claims 7 to 11, wherein the ballistic resistant curved shaped article is a ballistic resistant helmet shell or a radome.

13. The ballistic resistant helmet shell of claim 12 wherein the ballistic resistant helmet shell has an ear-to-ear stiffness of at most 5mm measured 24 hours after 25 compression cycles at 200 lb.

14. The ballistic resistant helmet shell of claim 12 or 13 wherein the ballistic resistant helmet shell has a blunt impact performance of less than 110G when measured in accordance with DOT FMVSS 218.

15. A ballistic resistant helmet comprising a ballistic resistant helmet shell according to any one of claims 12 to 14.

Examples

The comparative experiment was repeated except that there were 42 composite sheets comprising orthogonally stacked monolayers of unidirectionally arranged ultrahigh molecular weight polyethylene fibers having a yarn tenacity of about 40.5cN/dtex embedded in a polyethylene resin which is a neutralized ethylene acrylic acid copolymer. The acrylic acid level of the copolymer was about 10% by weight, whereby the neutralization of the carboxylic acids was over 98% and consisted of about 17 mol% ammonia with 83 mol% potassium counter ion. The melt flow index of the dried neutralized copolymer was 4.5g/10min (21.6kg, 190 ℃). The neutralized copolymer has a peak melting temperature at 85 ℃ and a modulus at 25 ℃ and 110 ℃ as measured by DMTA of 150MPa and 0.7MPa, respectively. The matrix content of the composite sheet was about 13 wt% and the areal density was about 126g/m²And a thickness of about 130 microns the lamination mode as in the comparative experiment was used except that 34 plies of size 53cm × 53cm had been used the areal density of the lamination was about 5.4kg/m². Make the pile upThe layers were subjected to the same compression molding step as the comparative experiment.

The results are shown in table 1.

TABLE 1

The results show that the helmet shell of the present invention, which has considerable ballistic properties and an ear-to-ear stiffness of less than 5mm, has an average blunt impact deceleration of about 93G. Furthermore, surprisingly, the helmet shell of the present invention has an improved backface signature.