无纺布用PP专用料,门槛不在强度、不在韧性,在可纺性与灰分。无纺布基材是石化厂纺丝级 PP 切片,改性造粒线接不住切片本体,只能做驻极母粒、亲水母粒与功能母粒。这篇把纺粘/熔喷对切片的要求、熔喷料检测口径与验证顺序摆清楚。
- 错开篇:→《晶圆运输盒缓冲垫用 POE 发泡 PP》(PP-A19,走洁净度与不脱屑)、→《农用地膜棚膜用什么改性PP》(PP-A48,走耐候增韧)
"无纺布用 PP,你们有切片吗?"
一个做卫材的采购这么问我。后半句是:要的是纺丝级 PP 切片原包,不是改性粒子。
这句话把我方直接挡在了门口——因为无纺布用PP专用料的基材,是石化厂纺丝级 PP 切片(聚合级原生切片),走的是化纤 / 无纺布通道,不是改性PP 造粒线的产品形态。客户买的是"切片"或"布",不是"改性粒子"。
先把这件事说在前面,比硬接一张单有用。
但更该讲清的是本篇主线:可纺性与灰分才是门槛——不是强度,不是韧性。 切片里那点灰分和杂质,决定喷丝板结不结垢、纤维断不断丝;多数人以为无纺布拼的是"布够不够强",真正卡工艺的是那零点零几的灰分。
一、无纺布用PP专用料的工况六维:灰分比强度更该先问
结论先说:六个维度里,最该先问的不是"强度多少",是"灰分多少、含湿多少、能不能稳定纺丝"。无纺布的评价对象是"丝"和"网",不是"块"。
| 维度 | 实际工况 | 对材料的要求 |
|---|
| 温度 | 纺粘法螺杆挤出约 230~280℃、熔体管约 250~290℃;熔喷法模头常落在 200~300℃ 区间;热轧(热粘合)区约 140~160℃;水刺为常温高压水(不靠热) | 熔体要在高温下稳定不降解;热稳定性 Td ≥300℃ 量级是公开门槛 |
| 载荷 | 牵伸气流速度:纺粘为几千米/分级,熔喷可达亚音速级;纤网克重常见 10~150 g/m²;纤维细度纺粘约 1~5 μm、熔喷可更细 | 牵伸均匀、纤网不破;细度越细对熔体稳定性要求越高 |
| 介质 | 卫材接触尿液、汗液;医用接触血液、酒精、药液;部分做过滤介质 | 医用与卫材走合规,不是力学 |
| 寿命 | 多为一次性使用;熔喷过滤布的关键寿命指标是驻极体电荷保持——常温/高温高湿(60℃/90% RH)储存 72 h 电荷衰减 ≤10% | 过滤效率的"寿命"看电荷衰减,不看拉伸 |
| 外观 | 布面均匀、无并丝、无晶点、无异味、无焦料 | 颗粒外观按 SH/T 1541.1:无明显色差、无机械杂质、无焦料 |
| 合规 | 医用级过细胞毒性 ISO 10993-5、微生物限度 GB 15979;食品/婴儿接触走对应食品接触与迁移要求 | 合规是入场项,不是加分项 |
表注:温度、牵伸气流与克重为公开技术资料转述(B 级),用于说明量级;具体门限须写进供需双方约定的牌号规格。六维里"寿命"对熔喷布不是"用多久不破",是"电荷撑多久不掉"。
二、纺粘PP与熔喷料两条工艺:基材是石化厂的活,母粒才是我们的落点
结论先说:纺粘和熔喷是两条工艺,对切片的熔指要求差出一个数量级;但共同点是——基材切片都归石化厂,改性造粒线能接的是母粒这一段。
先把边界说在前面:无纺布用PP专用料的基材,是石化厂按纺丝级设计的大装置专用料,不是改性PP 造粒线的产品。 等规度、分子量分布、灰分、挥发分这些指标,在聚合端和精制端就定下来了,下游共混补不上去。所以"切片本体"这一格,是石化厂的活。
| 项 | 纺粘法(spunbond) | 熔喷法(meltblown) |
|---|
| 熔融指数 MFI | 25~40 g/10min | 400~1500 g/10min |
| 分子量分布宽度 Mw/Mn | < 4~5 | 窄分布 |
| 熔点 | 164~170℃(纯等规 PP 为 176℃) | 同 |
| 密度 | 0.91 g/cm³ | 同 |
| 等规度 | 不低于 96% | 同 |
| 灰分 | 不高于 0.025% | 更低 |
| 含湿量 | 不高于 0.05% | 同 |
据公开技术资料(B 级)整理。这张表最反直觉的一格是灰分:熔喷法要的 MFI 比纺粘高一个数量级(400~1500 vs 25~40),但灰分要求反而更严。原因在工艺——熔喷模头喷丝孔更细、牵伸更猛,一点杂质就能堵板、断丝。
2.1 一个必须当面说清的口径冲突:熔喷料 MFR 到底是多少
这里要停一下,因为公开资料互相打架。 上表把熔喷料 MFR 写成"400~1500 g/10min",这是按过氧化物可控流变法生产的熔喷专用料规格(GB/T 30923 体系)的常见量级。但另一份公开资料把熔喷料 MFR 写成"常规 15~35 g/10min"——这与"400~1500"明显矛盾。
不要回避,也不要替读者选一个漂亮数字。处理方式是把话说清楚:这是两个不同口径——一个是按可控制流变法生产的专用料规格(高 MFR,对应高端熔喷布),另一个是不同资料对同一名称"熔喷料"的宽泛表述(中低 MFR,对应部分普通纺粘/熔喷混用或老旧牌号口径)。真实门限必须以供需双方约定的牌号规格为准。
2.2 改性造粒线能参与的三块:切片本体不做,母粒做
明确写:切片本体不在我们能做的范围内。 改性PP 造粒线能接的是三块母粒方向:
1. 驻极母粒方向——熔喷布过滤效率的关键助剂,靠驻极把电荷"挂"在纤维上提升捕获效率;
2. 亲水母粒方向——卫材用(尿不湿面层、卫生巾面层要求亲水导流,不能让液滴停在表面);
3. 抗静电 / 柔软 / 色母等功能母粒方向——按终端用途补表面与功能。
一句话判断经验:这类询盘先分清客户要的是"切片"还是"母粒"——要原生切片的直接指到石化厂,要母粒的才轮到我们这一步。把这条线讲在前面,客户反而更愿意把能接的那一段交过来。
三、★ 选型判据表:可纺性的九道关,每关都带验证方法
结论先说:这张表第一项不是强度,是等规度与 MFR 稳定性;最值钱的是灰分、DTBP 残留和驻极体衰减三行——它们决定"能不能纺"和"布能不能用",不是"布够不够强"。
| 指标 | 门限值(典型) | 验证方法·标准号 | 常见失效 | 通行解法 |
|---|
| 等规度 | 不低于 96% | 核磁或正庚烷萃取法(行业公开方法) | 结晶过快、纺丝断头 | 由石化厂牌号定 |
| MFR / MFI | 纺粘 25~40;熔喷 400~1500 g/10min | GB/T 3682.1(230℃/2.16 kg) | 熔体太稀/太稠,纤网不均 | 按工艺选档,见 §2.1 口径说明 |
| 熔体流动稳定性 MFRΔ | 波动 ≤±10% | GB/T 3682.1 多炉批复测 | 断丝、纤网厚薄不均 | 控批次一致性 |
| 灰分 | 纺粘 ≤0.025%;熔喷按 GB/T 30923 体系要求 ≤0.03%(更低) | GB/T 9345.1 | 喷丝板结垢、断丝 | 高纯催化 + 滤净 |
| 挥发分 | ≤0.1% | GB/T 2914 | 气泡丝、加工异味 | 低挥发牌号 |
| DTBP 残留 | ≤150 mg/kg | GB/T 30923-2022 附录 A 气相色谱法 | 交联、黄变、安全风险 | 控过氧化物降解剂量 |
| 分子量与分布 | Mw ≈3×10⁵~5×10⁵,PDI ≤3.5(熔喷);纺粘 Mw/Mn <4~5 | ISO 16014-4 高温 GPC | 牵伸不均、细度失控 | 窄分布牌号 |
| 熔点与热稳定性 | 熔点 160~170℃;热稳定性 Td ≥300℃ | 熔点 GB/T 19466.3 | 高温降解、黄变 | 控热氧稳定体系 |
| 驻极体电荷衰减 | 常温/高温高湿(60℃/90% RH)储存 72 h 衰减 ≤10% | 表面电荷密度(静电电位计)跟踪 | 过滤效率随时间掉 | 驻极母粒 + 工艺 |
| 气味 | ≤2 级 | T/CPPIA 5-2021 附录 A(三角瓶/气味瓶法,≥3 人评定) | 卫材异味投诉 | 低气味牌号 |
| 颗粒外观 | 无明显色差、无机械杂质、无焦料 | SH/T 1541.1 | 并丝、晶点 | 牌号洁净管控 |
| 纤维断裂强度 | 公开口径 ≥3.5 cN/dtex | 单纤强伸测试(行业公开方法) | 布身偏软、破洞 | 由基材与工艺定 |
文字版结论:九道关里,灰分、DTBP 残留、驻极体衰减三行是同行抄不走的硬信息单元。 基材段(等规度、MFR、灰分、分子量)不过,找石化厂换牌号;母粒段(驻极、亲水、功能)不过,才是我们这一侧要解的题。
四、常见失效与根因:最容易背锅的是"强度不够",其实是灰分
结论先说:这类件上四类失效,有三类的第一反应都会归错因——先怪"料不强",其实根因在灰分、在驻极体衰减、在 MFR 口径没对齐。
失效一:喷丝板频繁结垢、老断丝。 第一反应常是"切片强度不够"。错。根因绝大多数在灰分与机械杂质——灰分一高,喷丝孔边缘积垢、熔体流动性变差,断丝随之而来。可纺性看的是灰分与分子量分布,不是拉伸强度。 这一步该查 GB/T 9345.1 灰分和 ISO 16014-4 分子量分布,不是去比强度。
失效二:熔喷布刚下线的过滤效率够,放一阵就掉。 根因不是纤维本身,是驻极体电荷衰减——常温/高温高湿下 72 h 衰减一旦超过 10%,捕获效率就垮。这一条在出厂检验单上通常不出现,是"事后才发现"的那一类。
敢否定一个常见做法:以为"MFR 越高越好、熔指越大布越细"。错。熔指调太高要靠更多过氧化物降解,带来的是 DTBP 残留上升、热稳定性下降、黄变与交联风险。高 MFR 是手段不是目的,残留在 150 mg/kg 以下、Td ≥300℃ 才是底线。追高 MFR 追到残留超标,是这类件上最隐蔽的错法。
失效三:以为"强度够就万事大吉"。 无纺布/卫材用切片,门槛本就不在强度与韧性,在可纺性与洁净度;前面九道关过了,强度自然到位,单追强度没用。
失效四:询盘直接甩一个"熔喷料 MFR"数字来锁价。 见 §2.1——这个数字可能在 15~35 与 400~1500 两个口径之间摇摆。没对齐口径就报方案,等于拿别人的模糊当自己的承诺。
五、验证顺序:从颗粒外观到布面性能,逐级不过就退回
结论先说:验证顺序是"切片入场项 → 纺丝试做项 → 布面性能项"三段;顺序反了,最贵的失败会落在最后一步(整卷布)。
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① 颗粒外观 色差、机械杂质、焦料(SH/T 1541.1)
↓ 有杂质/焦料 → 退回牌号洁净管控
② MFR 及波动 GB/T 3682.1,多炉批复测 MFRΔ ≤±10%
↓ 波动超门限 → 退回批次一致性
③ 灰分与挥发分 GB/T 9345.1(灰分);GB/T 2914(挥发分)
↓ 灰分超 / 挥发超 → 退回高纯牌号
④ DTBP 残留 GB/T 30923-2022 附录 A 气相色谱法,≤150 mg/kg
↓ 残留超 → 退回过氧化物降解剂量管控
⑤ 分子量与分布 ISO 16014-4 高温 GPC(Mw、PDI)
↓ 分布过宽 → 退回窄分布牌号
⑥ 熔点与热稳定性 GB/T 19466.3(熔点);Td ≥300℃
↓ 热稳定性不足 → 退回热氧稳定体系
⑦ 纺丝试做 / 成网检验 小试喷丝、看断丝率与纤网均匀性
↓ 断丝/并丝 → 退回 ③ 与 ⑤,重排牌号
⑧ 布面性能 克重、断裂强力、透气、过滤效率;驻极体 72 h 衰减
↓ 过滤效率掉 → 退回驻极母粒与驻极工艺
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最常被跳过的两处:跳过 ①②③④⑤ 直接做 ⑦,把材料侧的问题留到试做侧暴露;跳过 ⑧ 的驻极体衰减,一次"事后才发现"就是整批布的退货。
六、反向诚实:这四类询盘该直接找石化厂或布厂,我们接不住
结论先说:这个方向的主体不在改性造粒线上。把"接不住"写清楚,比硬接一张单有用。
| 出现的情况 | 该找谁 |
|---|
| 只要原生切片(纺丝级 PP 切片原包) | 石化厂 / 切片代理商 |
| 要纺丝—成网—热轧(或水刺)整线产品 | 无纺布厂 |
| 要求整卷无纺布性能承诺(克重、断裂强力、透气、过滤效率) | 无纺布厂(承诺对象是布,不是粒子) |
| 要求驻极处理后的过滤效率与电荷衰减承诺 | 无纺布厂 / 驻极设备方 |
一条判断经验:这类询盘先分清客户要的是"切片"还是"母粒"——要切片的直接指到石化厂,要母粒的才轮到我们这一步。我们不做切片本体,也不冒充能做整卷布的性能承诺。
那我们能接的是哪一块? 边界画在三处:① 驻极母粒(熔喷布过滤效率的关键助剂);② 亲水母粒(卫材面层导流);③ 抗静电 / 柔软 / 色母等功能母粒。三块都是"母粒",不是"切片本体"。
七、换料风险清单:纺丝与成网侧的清单,不是注塑模具清单
结论先说:无纺布方向的换料风险集中在"纺丝温度窗口、喷丝板与过滤网、牵伸气流、成网与热轧/水刺、驻极工序"五块,跟注塑件的收缩率、浇口是两套清单。
| 要动的项 | 需要确认什么 | 不做会怎样 |
|---|
| 纺丝温度窗口 | 螺杆与熔体管温度分布是否匹配新料;热稳定性 Td ≥300℃ 是否还成立 | 降解、黄变、断丝 |
| 喷丝板与过滤网 | 喷丝孔孔径与过滤精度是否匹配灰分/杂质水平 | 堵板、并丝、晶点 |
| 牵伸气流 | 纺粘/熔喷的牵伸风速与温湿度是否还稳 | 纤网厚薄不均、细度失控 |
| 成网与热轧/水刺 | 热轧温度(约 140~160℃)或水刺水压是否还适配 | 布面不匀、粘合不足、破洞 |
| 驻极工序 | 驻极电压与工艺是否匹配母粒;72 h 衰减能否 ≤10% | 过滤效率掉、电荷衰减超标 |
| 色差 / 外观 | 换母粒后布面色差与均匀性 | 外观降等 |
| 验证顺序 | 颗粒外观 → MFR → 灰分 → DTBP → 分子量 → 纺丝试做 → 布面 | 风险全压到整卷布那一步爆发 |
换料要动的是纺丝温度、喷丝板与过滤网、牵伸气流、成网与驻极五块,其中最该先谈的是验证顺序。跳过材料入场项直接做整卷试做,等于用整批布的成本去发现一个切片能测出来的问题。
八、一页纸汇报对照表:无纺布卫材选材可以直接贴进 PPT
结论先说:判断标准只有一条——客户拿这张表,能不能在一次会议里把"找石化厂还是找我们"定下来。
| 场景 | 推荐路线 | 关键指标 | 验证标准 | 需先确认的条件 |
|---|
| 纺粘无纺布(卫材/包装基布) | 石化厂纺丝级 PP 切片(MFI 25~40) | 等规度 ≥96%、灰分 ≤0.025%、MFRΔ ≤±10% | GB/T 3682.1、GB/T 9345.1 | 要切片还是要母粒 |
| 熔喷过滤布(口罩/滤材) | 石化厂熔喷专用料(高 MFR)+ 驻极母粒 | MFR 口径对齐、DTBP ≤150 mg/kg、72 h 衰减 ≤10% | GB/T 30923-2022 附录 A、静电电位计 | 过滤等级、驻极工艺归属 |
| 卫材亲水面层(尿不湿/卫生巾) | 基材切片 + 亲水母粒 | 亲水导流、低气味 ≤2 级 | T/CPPIA 5-2021 附录 A | 接触体液合规 |
| 医用防护/手术衣 | 医用级基材 + 驻极/功能母粒 | 细胞毒性 ISO 10993-5、微生物 GB 15979 | 对应医用标准 | 无菌与微生物限度要求 |
| 抗静电/柔软/染色无纺布 | 基材切片 + 功能母粒 | 表面电阻、柔软度、色差 | 按终端约定 | 功能由谁承担 |
文字版结论:五条场景里,第一、二、三列都是"基材找石化厂、母粒找我们"的组合。最有用的是最后一列——它决定报出去的话能不能兑现。
九、这个方向上最容易出问题的,往往不是料
无纺布用PP专用料这个方向上的公开技术讨论里,最常被提到的两类现场问题是喷丝板结垢断丝与熔喷布过滤效率随时间衰减。而这两类问题里,由"切片强度不够"引起的比例并不高——基材判据在牌号资料里写得很清楚,选了位就基本定了;难的是灰分/杂质与驻极体衰减这两侧。
公开判据也很明确:灰分按 GB/T 9345.1 测、挥发分按 GB/T 2914 测、DTBP 残留按 GB/T 30923-2022 附录 A 气相色谱法测(≤150 mg/kg)、分子量分布按 ISO 16014-4 高温 GPC 测、驻极体衰减用静电电位计在 60℃/90% RH 下跟踪 72 h。这几项里,只有驻极体衰减是"时间一到才暴露"的,评价周期必须留足。
行业通行的做法是把三件事一起定:基材牌号按可纺性选,母粒按终端功能配(驻极/亲水/抗静电),驻极工序单独验衰减。关键不在谁的料更强,在切片洁净度、母粒功能、驻极工艺三件事能不能同时对上。
宁波市科隆新材料有限公司在这个方向上常供的是改性PP 粒子里的这几段:驻极母粒方向、亲水母粒方向、抗静电/柔软/色母等功能母粒方向,按件的工况给母粒配方与加量建议,可以陪客户做小样比对与验证顺序对接。纺丝级 PP 切片本体与整卷无纺布性能承诺这两段不在我们能接的范围内。
常见问答
问:无纺布能不能直接用改性 PP 粒子做?
答:做得出来,但主流不是这么用的。无纺布基材是石化厂纺丝级 PP 切片,可纺性与灰分在聚合端定;改性造粒线站得住的位置是驻极母粒、亲水母粒与功能母粒这三段。
问:熔喷料 MFR 到底该锁哪个数?
答:先对齐口径。按可控制流变法的专用料规格常见 400~1500 g/10min;另有资料把"熔喷料"宽泛写成 15~35 g/10min。真实门限以供需双方约定的牌号规格为准,不要拿二手数字拍板。
问:过滤效率刚下线够、放一阵就掉,是不是布不够强?
答:不是。多半是驻极体电荷衰减——常温/高温高湿 72 h 衰减超过 10%,捕获效率就垮。该查驻极母粒与驻极工艺,不是去追纤维强度。
| 工况 | 关键判据 | 我方常规供应方向 |
|---|
| 纺粘无纺布基材 | 等规度、灰分、MFRΔ | 不供切片本体;功能母粒方向(如需) |
| 熔喷过滤布 | DTBP 残留、驻极体 72 h 衰减 | 驻极母粒方向 |
| 卫材亲水面层 | 亲水导流、低气味 ≤2 级 | 亲水母粒方向 |
| 抗静电/柔软/染色无纺布 | 表面电阻、柔软度、色差 | 抗静电/柔软/色母等功能母粒方向 |
想提醒一句:无纺布出问题,最常见的错法是先换料。结垢、断丝、效率掉——每一条的原因都不止一个。先定位是灰分、是驻极体、还是口径没对齐,再换料;顺序反了,往往换了几轮还在原地。
十、最后说三句
第一,无纺布用PP专用料的门槛是灰分和可纺性,不是强度。 切片里那零点零几的灰分,决定喷丝板结不结垢、纤维断不断丝。
第二,熔喷料最硬的一条信息是 DTBP 残留(≤150 mg/kg),按 GB/T 30923-2022 附录 A 气相色谱法测。 追高 MFR 追到残留超标,是这类件上最隐蔽的错法。
第三,先分清"切片还是母粒"。 要原生切片找石化厂,要母粒才轮到改性造粒线这一步;过滤效率撑不撑得住,最终看驻极体 72 h 衰减。
关于我们
一颗 PP 粒子出厂时,只是一颗粒子。
它变成保险杠、冰箱内胆、洗衣机桶、餐盒,中间隔着一整套方案——基材选哪档、填充加多少、增韧走哪条路、收缩压不压得住、气味过不过得了门。
PP special material for non-woven fabrics: the threshold is not in strength or toughness, but in spinnability and ash content. The non-woven fabric substrate is PP pellets of spinning grade from petrochemical plants. The modification and pelletizing line cannot handle the pellets themselves and can only produce electret masterbatch, hydrophilic masterbatch, and functional masterbatch. This article clarifies the requirements for spunbond/meltblown fibers for pellets, the testing standards for meltblown materials, and the order of verification.
- Misaligned chapters: → 'POE Foamed PP for Wafer Transport Box Cushion' (PP-A19, focusing on cleanliness and non-flaking), → 'What Modified PP to Use for Agricultural Film Greenhouse Covers' (PP-A48, focusing on weather resistance and toughness)
PP for non-woven fabric, do you have chips?
A procurement person from a company making sanitary products asked me this. The second half of the sentence is: What is needed is fiber-grade PP pellets in their original packaging, not modified pellets.
This sentence directly blocked us at the door—because the substrate for non-woven fabric uses PP special material, which is petrochemical plant spun-grade PP chips (polymer-grade virgin chips), going through the chemical fiber/non-woven fabric channel, not the product form of modified PP granules. The customer buys 'chips' or 'fabric,' not 'modified pellets.'
It's better to bring this matter up first; it's more useful than forcibly taking an order.
But what should be clarified more is the main focus of this article: spinnability and ash content are the thresholds—not strength, not toughness. The tiny amount of ash and impurities in the slice determines whether the spinneret plate will foul and whether the fibers will break or not; most people think that nonwoven fabrics compete based on 'whether the fabric is strong enough,' but what really restricts the process is that fractional ash content, that 0.0-something percent.
1. Six operating conditions of PP special material for non-woven fabric: Ash content and tensile strength should be asked first
Conclusion first: Among the six dimensions, the first thing to ask is not 'how strong it is,' but 'how much ash, how much moisture, and whether it can be stably spun.' The evaluation of nonwoven fabric is based on the 'fiber' and the 'web,' not the 'block.'
| Dimension | Actual operating conditions | Requirements for the materials |
|---|
| Temperature | Spunbond screw extrusion is about 230~280℃, melt pipe about 250~290℃; the meltblown die head usually falls in the 200~300℃ range; the hot rolling (hot bonding) area is about 140~160℃; spunlace uses high-pressure water at room temperature (without heat) | The melt must remain stable at high temperatures without degrading; the thermal stability Td ≥ 300°C is the threshold level disclosed publicly. |
| Load | Draft airflow speed: Spunbond is at several thousand meters per minute, meltblown can reach subsonic levels; common web basis weight is 10~150 g/m²; fiber fineness: spunbond about 1~5 μm, meltblown can be even finer | Stretching is uniform, and the fiber web does not break; the finer the fineness, the higher the requirement for melt stability. |
| Medium | Pharmaceutical materials come into contact with urine and sweat; medical uses involve contact with blood, alcohol, and medicinal liquids; some are used as filtration media. | Medical and sanitary materials follow compliance, not mechanics |
| Lifespan | Mostly for single use; the key lifespan indicator of meltblown filter fabric is electret charge retention — charge decay ≤10% after 72 hours of storage at room temperature/high temperature and high humidity (60°C/90% RH) | The 'lifespan' of filtration efficiency is judged by charge decay, not by stretching. |
| Appearance | The surface of the cloth is uniform, with no pilling, no crystalline spots, no odor, and no scorched material. | Granule appearance according to SH/T 1541.1: no obvious color difference, no mechanical impurities, no burnt material |
| Compliance | Medical-grade ultra-fine cytotoxicity ISO 10993-5, microbial limit GB 15979; food/baby contact follows the corresponding food contact and migration requirements | Compliance is an entry requirement, not an extra credit. |
Note: The temperature, draw air, and basis weight are restated from publicly available technical information (Class B) to illustrate the scale; specific thresholds must be included in the grade specifications agreed upon by both supplier and purchaser. In Six Dimensions, 'lifespan' for meltblown fabric does not mean 'how long it lasts without breaking,' but 'how long the charge lasts before dropping.'
2. Two processes for spunbond PP and meltblown material: the base material comes from the petrochemical plant, while the masterbatch is our focus.
Conclusion first: Spunbond and meltblown are two different processes, and the melt flow index requirements for the chips differ by an order of magnitude; but the common point is that the base material chips all go to petrochemical plants, and the part that the modified pelletizing line can handle is the masterbatch.
Let's clarify the boundaries first: the base material for non-woven fabric uses PP-grade material specifically for polypropylene, which is designed for large-scale units at petrochemical plants for spinning-grade production, not a product from a modified PP pelletizing line. Specifications such as isotacticity, molecular weight distribution, ash content, and volatiles are determined at the polymerization and refining stages, and downstream blending cannot make up for them. Therefore, the 'pellet body' part is the responsibility of the petrochemical plant.
| item | Spunbond method | Meltblown method (meltblown) |
|---|
| Melt Flow Index (MFI) | 25~40 g/10min | 400~1500 g/10min |
| Molecular weight distribution width Mw/Mn | < 4~5 | narrow distribution |
| Melting point | 164~170℃ (176℃ for pure isotactic PP) | Same |
| Density | 0.91 g/cm³ | Same |
| standards and measures | Not less than 96% | Same |
| Ash content | Not higher than 0.025% | Lower |
| Moisture content | Not higher than 0.05% | Same |
Compiled from publicly available technical data (Class B). The most counterintuitive entry in this table is ash content: the MFI required for the meltblown process is an order of magnitude higher than that for the spunbond process (400~1500 vs 25~40), yet the ash content requirement is actually stricter. The reason lies in the process—meltblown die nozzles have finer holes and greater drawing, and even a small amount of impurity can block the die or break the fibers.
2.1 A Caliber Conflict That Must Be Clarified in Person: What Exactly Is the MFR of Meltblown Material
We need to pause here because the public information contradicts each other. The table above lists the MFR of melt-blown material as "400~1500 g/10min," which is the common range for melt-blown specific materials produced by the peroxide-controlled rheology method (according to the GB/T 30923 system). However, another public source lists the MFR of melt-blown material as "conventional 15~35 g/10min" — which is clearly in conflict with "400~1500".
Do not avoid it, and do not pick a nice number for the reader. The way to handle it is to state it clearly: these are two different calibers—one is the special material specification produced according to the controllable rheology method (high MFR, corresponding to high-end meltblown fabric), and the other is a broad description of the same name 'meltblown material' by different sources (medium-low MFR, corresponding to some ordinary spunbond/meltblown blends or older grade calibers). The actual threshold must be based on the grade specifications agreed upon by both supply and demand parties.
2.2 Three parts that the modified granulation line can participate in: the slicer body is not done, the masterbatch is done
Clearly state: Slicing the material itself is beyond what we can do. The modified PP granulation line can handle three types of masterbatch directions:
1. Electret masterbatch direction — a key additive for the filtration efficiency of melt-blown fabric, relying on the electret to 'attach' the charge to the fibers to improve capture efficiency;
2. Hydrophilic masterbatch direction — for Eizai use (the surface layer of diapers and sanitary napkins requires hydrophilic guidance to prevent liquid droplets from staying on the surface);
3. Anti-static / soft / color masterbatch and other functional masterbatch directions — supplement surface and functionality according to end-use.
One-sentence experience judgment: For this type of inquiry, first distinguish whether the customer wants 'flakes' or 'masterbatch'—if they want virgin flakes, directly refer them to the petrochemical plant; only if they want masterbatch does it come to our stage. By explaining this line upfront, customers are actually more willing to hand over the part we can handle.
3. ★ Selection Criteria Table: Nine Gates of Spinnability, Each with Verification Method
Conclusion first: The first item in this table is not strength, but isotropy and MFR stability; the most valuable ones are ash content, DTBP residue, and electret decay—these determine 'whether it can be spun' and 'whether the fabric can be used,' not 'whether the fabric is strong enough'.
| Indicator | Threshold Value (Typical) | Verification Method · Standard Number | Common Failures | Common solution |
|---|
| standards and measures | Not less than 96% | Nuclear magnetic or n-heptane extraction method (industry public method) | Crystallization too fast, spinning break | Determined by the petrochemical plant brand |
| MFR / MFI | Spunbond 25~40; Meltblown 400~1500 g/10min | GB/T 3682.1 (230℃/2.16 kg) | Melt is too thin/thick, fiber network is uneven | Select the grade according to the process, see §2.1 for caliber specifications |
| Melt Flow Stability MFRΔ | Fluctuation ≤ ±10% | GB/T 3682.1 Multi-Furnace Batch Test Approval | Broken threads, uneven thickness of the fiber web | Control batch consistency |
| Ash content | Spunbond ≤0.025%; Meltblown according to GB/T 30923 system requirements ≤0.03% (lower) | GB/T 9345.1 | Spinneret scaling and broken filaments | High-Purity Catalysis Filtration |
| Volatile matter | ≤0.1% | GB/T 2914 | Bubble threads, processing odor | Low volatility grade |
| DTBP residue | ≤150 mg/kg | GB/T 30923-2022 Appendix A Gas Chromatography Method | Crosslinking, yellowing, safety risks | Dose for controlling peroxide degradation |
| Molecular Weight and Distribution | Mw ≈ 3×10⁵~5×10⁵, PDI ≤ 3.5 (meltblown); spunbond Mw/Mn < 4~5 | ISO 16014-4 High-Temperature GPC | Uneven stretching and loss of fineness control | Narrow distribution grade |
| Melting Point and Thermal Stability | Melting point 160~170℃; thermal stability Td ≥300℃ | Melting point GB/T 19466.3 | High-temperature degradation, yellowing | Controlled Thermal-Oxidation Stabilization System |
| Electret charge decay | Storage at room temperature/high temperature and high humidity (60°C/90% RH) for 72 h attenuation ≤10% | Surface charge density (electrostatic voltmeter) tracking | Filtration efficiency decreases over time | Electret masterbatch process |
| smell | ≤ Level 2 | T/CPPIA 5-2021 Appendix A (Erlenmeyer/Bottle Odor Method, ≥3 Evaluators) | Complaints about unusual odor from Eisai products | Low-odor grade |
| Granule appearance | No obvious color difference, no mechanical impurities, no burnt material | SH/T 1541.1 | Filaments and crystal points | Grade Cleanliness Control |
| Fiber breaking strength | Open-end fineness ≥3.5 cN/dtex | Single Fiber Strength Extension Test (Industry Public Method) | The fabric is relatively soft and has holes | Determined by the substrate and process |
Text version conclusion: Among the nine sections, the three lines of ash content, DTBP residue, and electret decay are hard information units that peers cannot copy. The substrate segment (consistency, MFR, ash content, molecular weight) is not a big deal; you can just get the petrochemical plant to change the grade. But the masterbatch segment (electret, hydrophilicity, functionality) is what we on this side really need to figure out.
4. Common failures and root causes: The most common scapegoat is 'insufficient strength,' but it is actually the ash content.
Conclusion first: There are four types of failures in this kind of part. For three of them, the initial reaction always misattributes the cause — first blaming the 'material not strong enough' — but the real root causes lie in the ash content, the electret decay, and the misalignment of the MFR gauge.
Failure 1: Spinneret frequently scaling and breaking filaments. The usual first reaction is 'insufficient slice strength.' Wrong. The root cause is mostly ash content and mechanical impurities—high ash leads to scaling at the spinneret holes, poor melt flow, and consequently broken filaments. Spinnability depends on ash content and molecular weight distribution, not tensile strength. At this step, one should check GB/T 9345.1 for ash content and ISO 16014-4 for molecular weight distribution, not compare tensile strength.
Failure 2: The filtration efficiency of meltblown fabric is sufficient right after production, but it decreases after a while. The root cause is not the fiber itself, but the decay of the electret charge—at normal temperature/high temperature and high humidity, once the decay exceeds 10% within 72 hours, the capture efficiency collapses. This is usually not reflected in the factory inspection report and is the kind that is 'discovered afterward.'
Dare to question a common practice: thinking that 'the higher the MFR, the better; the higher the melt index, the finer the fabric.' Wrong. Adjusting the melt index too high requires more peroxide degradation, resulting in increased DTBP residue, decreased thermal stability, yellowing, and risk of cross-linking. A high MFR is a means, not an end; the baseline is having residue below 150 mg/kg and Td ≥ 300°C. Chasing a higher MFR to the point where residue exceeds the limit is the most hidden mistake for this type of product.
Failure Three: Thinking 'as long as the strength is enough, everything is fine.' For nonwoven fabrics/medical supplies slices, the threshold is not in strength and toughness, but in spinnability and cleanliness; if the first nine checkpoints are passed, the strength will naturally be sufficient, so solely chasing strength is useless.
Invalid point four: Directly throwing out an 'meltblown material MFR' number in an inquiry to lock the price. See §2.1 — this number may fluctuate between two ranges, 15~35 and 400~1500. Reporting a plan without aligning the caliber is equivalent to taking someone else's ambiguity as your own commitment.
5. Verification sequence: from the appearance of the particles to the fabric performance, if it does not pass at any level, it will be returned.
Conclusion first: The verification sequence is in three stages: 'slice entry items → spinning trial items → fabric performance items'; if the order is reversed, the most expensive failure will occur in the final step (the whole roll of fabric).
`
① Granule Appearance Color difference, mechanical impurities, burnt material (SH/T 1541.1)
↓ Impurities/charred material → Return to grade clean control
② MFR and Fluctuation GB/T 3682.1, multiple furnace batch approval measurement MFRΔ ≤ ±10%
↓ Fluctuation exceeds threshold → Revert batch consistency
③ Ash Content and Volatile Matter GB/T 9345.1 (Ash Content); GB/T 2914 (Volatile Matter)
↓ Excess ash / excess volatility → return to high-purity grade
④ DTBP Residue GB/T 30923-2022 Appendix A Gas Chromatography Method, ≤150 mg/kg
↓ Residual excess → Return to peroxide degradation dosage control
⑤ Molecular Weight and Distribution ISO 16014-4 High-Temperature GPC (Mw, PDI)
↓ Distribution too wide → Return to narrow distribution grade
⑥ Melting Point and Thermal Stability GB/T 19466.3 (Melting Point); Td ≥ 300℃
↓ Insufficient thermal stability → Return to the thermo-oxidative stable system
⑦ Spinning trial / web formation inspection Small-scale spinning, check breakage rate and web uniformity
↓ Broken thread/entangled thread → Return to ③ and ⑤, reorder serial numbers
⑧ Fabric performance Basis weight, breaking strength, air permeability, filtration efficiency; electret 72 h decay
↓ Filtration efficiency drops → Return to electret masterbatch and electret process
`
The two most commonly skipped parts: skipping ①②③④⑤ and going straight to ⑦, leaving the material-side issues exposed to trial; skipping ⑧'s electret decay, only to find out 'after the fact' that the entire batch of cloth has to be returned.
6. Reverse honesty: For these four types of inquiries, they should directly contact petrochemical plants or fabric factories; we can't handle them.
Conclusion first: The main body in this direction is not on the modification granulation line. Clearly writing 'cannot catch' is more useful than rigidly connecting a single sheet.
| The situation that occurred | Who should I find |
|---|
| Only original pellets (spinning-grade PP pellets in the original package) | Petrochemical Plant / Slicing Agent |
| Spinning—Web forming—Hot rolling (or spunlace) whole line products | Non-woven fabric factory |
| Request performance commitment for the entire roll of non-woven fabric (grammage, tensile strength, breathability, filtration efficiency) | Non-woven fabric factory (the promise is to the fabric, not to the particles) |
| Requirements for filtration efficiency and charge decay commitment after electret treatment | Non-woven Fabric Factory / Electret Equipment Side |
A rule of thumb: For this kind of inquiry, first determine whether the customer wants 'flakes' or 'masterbatch'—if they want flakes, direct them straight to the petrochemical plant; only if they want masterbatch do we come into play. We do not produce flakes ourselves, nor do we pretend to guarantee the performance of whole rolls of fabric.
So which part can we handle? The boundaries are drawn in three areas: ① Electret masterbatch (a key additive for the filtration efficiency of meltblown fabric); ② Hydrophilic masterbatch (guides flow on the material's surface); ③ Functional masterbatches such as antistatic / softening / color masterbatch. All three are 'masterbatches,' not the 'sliced substrate.'
7. Material Change Risk List: A list for spinning and web forming, not an injection molding tool list
Conclusion first: The risks of changing materials in the non-woven fabric direction are concentrated in five areas: "spinning temperature window, spinneret and filter, drawing air flow, web formation and thermal calendering/water jet, and electret process", which are a completely different list from the shrinkage and gate issues of injection-molded parts.
| Items to move | What needs to be confirmed | What will happen if I don't do it? |
|---|
| Spinning temperature window | Does the temperature distribution of the screw and the melt tube match the new material; is the thermal stability Td ≥ 300°C still valid? | Degradation, yellowing, filament breakage |
| Spinneret and Filter Screen | Whether the spinneret aperture matches the filtration accuracy for ash/impurity levels | plugs, threading, crystal points |
| Stretching airflow | Are the drawing air speed and temperature and humidity of spunbond/meltblown still stable? | Inconsistent thickness of the fiber web and uncontrolled fineness |
| Mesh Forming and Hot Rolling/Water Spunlace | Is the hot rolling temperature (about 140~160°C) or hydroentangling water pressure still suitable? | Uneven fabric surface, insufficient adhesion, holes |
| Electret process | Whether the electret voltage matches the masterbatch process; whether the 72-hour decay can be ≤10% | Filtration efficiency dropped, charge decay exceeded the limit |
| Color difference / Appearance | Color difference and uniformity of the fabric after changing the masterbatch | Appearance downgrade |
| Verification order | Granule appearance → MFR → Ash content → DTBP → Molecular weight → Pilot spinning → Fabric surface | The entire risk is concentrated on the step of handling the whole roll of cloth. |
Changing materials involves adjustments to five areas: spinning temperature, spinneret and filter screen, drawing airflow, web formation, and electret, with the first thing to discuss being the verification sequence. Skipping the material intake step and directly doing a full-roll trial is equivalent to using the cost of an entire batch of fabric to discover a problem that could have been detected with a single slice.
8. One-page report comparison table: Non-woven fabric sanitary material selection can be directly pasted into the PPT
Conclusion first: There is only one criterion for judgment——whether the client can take this form and decide in a single meeting whether to 'go to a petrochemical plant or come to us.'
| Scene | Recommended Route | Key indicators | Verification Standard | Conditions that need to be confirmed first |
|---|
| Spunbond Nonwoven Fabric (Medical/Packaging Base Fabric) | Petrochemical plant spinning-grade PP pellets (MFI 25~40) | Crystallinity ≥96%, Ash content ≤0.025%, MFRΔ ≤±10% | GB/T 3682.1, GB/T 9345.1 | Do you want pellets or masterbatch? |
| Meltblown filter cloth (mask/filter material) | Petrochemical Plant Meltblown Special Material (High MFR) Electret Masterbatch | MFR caliber alignment, DTBP ≤150 mg/kg, 72 h decay ≤10% | GB/T 30923-2022 Appendix A, Electrostatic Voltmeter | Filter grade, electret process attribution |
| Eisai hydrophilic top layer (diapers/sanitary napkins) | Substrate slices Hydrophilic masterbatch | Hydrophilic drainage, low odor ≤ level 2 | T/CPPIA 5-2021 Appendix A | Compliance with exposure to bodily fluids |
| Medical protective/surgical gown | Medical-grade substrate Electret/functional masterbatch | Cytotoxicity ISO 10993-5, Microorganisms GB 15979 | Corresponding medical standards | Sterility and microbial limit requirements |
| Anti-static / Soft / Dyed Non-woven Fabric | Substrate Slice Functional Masterbatch | Surface resistance, softness, color difference | As agreed by the terminal | Who is responsible for the function |
Text version conclusion: In the five scenarios, the first, second, and third columns all consist of the combination 'the substrate goes to the petrochemical plant, the masterbatch comes to us.' The most useful is the last column—it determines whether what is reported can actually be realized.
9. In this area, the things that are most likely to go wrong are often not the materials.
In public technical discussions about PP-grade materials for nonwoven fabrics, the two most commonly mentioned on-site issues are spinneret fouling and broken filaments, and the decline in meltblown fabric filtration efficiency over time. However, among these issues, the proportion caused by 'insufficient slice strength' is not high—the substrate criteria are clearly stated in the grade data, and once the grade is selected, it is basically determined; the difficult part lies in ash/impurities and electret decay.
The publicly available criteria are also very clear: ash content is measured according to GB/T 9345.1, volatile matter is measured according to GB/T 2914, DTBP residue is measured according to Appendix A of GB/T 30923-2022 using gas chromatography (≤150 mg/kg), molecular weight distribution is measured by high-temperature GPC according to ISO 16014-4, and electret decay is tracked for 72 hours at 60°C/90% RH using an electrostatic potential meter. Among these items, only electret decay is "exposed only when the time is up," so the evaluation period must be sufficient.
The common practice in the industry is to decide on three things together: select the substrate grade based on spinnability, match the masterbatch according to the end-use function (electret/hydrophilic/antistatic), and test the decay of the electret process separately. The key is not whose material is stronger, but whether the three things—flake cleanliness, masterbatch function, and electret process—can align simultaneously.
Ningbo Kolon New Materials Co., Ltd. commonly supplies the following segments in this direction for modified PP pellets: electret masterbatch direction, hydrophilic masterbatch direction, antistatic/soft/color masterbatch and other functional masterbatch directions. They provide masterbatch formulations and dosage recommendations according to the working conditions, and can assist customers with small sample comparisons and verification sequence coordination. The performance commitments for spinning-grade PP chips themselves and entire rolls of non-woven fabric are not within the scope we can undertake.
Frequently Asked Questions
Question: Can non-woven fabric be made directly from modified PP pellets?
Answer: It can be done, but this is not the mainstream usage. The non-woven fabric substrate is spun-grade PP chips from petrochemical plants, and its spinnability and ash content are determined during polymerization; the positions where the modified pelletizing line holds are the electret masterbatch, hydrophilic masterbatch, and functional masterbatch.
Question: Which number should the MFR of melt-blown material actually lock onto?
Answer: First, align the standards. According to the specifications of specialized materials for controllable rheology, the common range is 400~1500 g/10min; other sources broadly list 'meltblown materials' as 15~35 g/10min. The actual threshold should be based on the grade specifications agreed upon by both suppliers and buyers, and do not make decisions based on second-hand figures.
Q: The filtration efficiency drops shortly after going online and decreases further after a while. Is it because the fabric isn't strong enough?
Answer: No. It is mostly electret charge decay — at normal/high temperature and high humidity, if the decay exceeds 10% in 72 hours, the capture efficiency will collapse. You should check the electret masterbatch and electret process, not chase after fiber strength.
| Operating condition | Key criterion | Our regular supply direction |
|---|
| Spunbond nonwoven fabric substrate | Moisture content, ash content, MFRΔ | Do not provide sliced body; functional masterbatch direction (if needed) |
| Meltblown Filter Fabric | DTBP residue, electret 72 h decay | Electret masterbatch direction |
| Eisai hydrophilic surface layer | Hydrophilic drainage, low odor ≤ level 2 | Hydrophilic Masterbatch Direction |
| Anti-static / Soft / Dyed Non-woven Fabric | Surface resistance, softness, color difference | Direction of functional masterbatches such as antistatic/softness/color masterbatch |
I want to give a reminder: when there is a problem with non-woven fabric, the most common mistake is to change the material first. Scaling, filament breakage, efficiency drop — each issue has more than one cause. First identify whether it is ash content, electret, or misaligned diameter, and then change the material; if the order is reversed, often after several rounds of changing, the problem remains the same.
Ten, Lastly, Say Three Sentences
First, the threshold for using PP specialized material for non-woven fabric is ash content and spinnability, not strength. The tiny fraction of ash in the pellets determines whether the spinneret will foul or not, and whether the fibers break or not.
Second, the hardest piece of information about meltblown material is the DTBP residue (≤150 mg/kg), measured by gas chromatography according to Appendix A of GB/T 30923-2022. Chasing a high MFR to the point of exceeding the residue limit is the most hidden mistake for this type of part.
Third, first distinguish between 'flakes or masterbatch.' If you need raw flakes, go to the petrochemical plant; if you need masterbatch, then it's the turn of the modification and granulation line. Whether the filtration efficiency holds up ultimately depends on the 72-hour decay of the electret.
About Us
A PP particle is just a particle when it leaves the factory.
It turns into bumpers, refrigerator liners, washing machine drums, and food containers, with an entire set of plans in between—what grade of base material to choose, how much filler to add, which path to take for toughening, whether shrinkage can be controlled, and whether the odor can pass the standard.